NEP: missing-data: Incorporate Ben's feedback, add section on 'shared masks'
NEP: missing-data: Incorporate Ben's feedback, add section on 'shared masks'

This includes an email comment from Ben about 'np.any' and 'np.all'.

dimasad/numpy,MSeifert04/numpy,Yusa95/numpy,ChanderG/numpy,Linkid/numpy,pdebuyl/numpy,mattip/numpy,WillieMaddox/numpy,utke1/numpy,BMJHayward/numpy,rherault-insa/numpy,BMJHayward/numpy,nbeaver/numpy,grlee77/numpy,matthew-brett/numpy,rherault-insa/numpy,has2k1/numpy,hainm/numpy,SiccarPoint/numpy,njase/numpy,WarrenWeckesser/numpy,CMartelLML/numpy,pelson/numpy,jankoslavic/numpy,empeeu/numpy,rmcgibbo/numpy,rgommers/numpy,Eric89GXL/numpy,moreati/numpy,kiwifb/numpy,sonnyhu/numpy,argriffing/numpy,WillieMaddox/numpy,b-carter/numpy,bmorris3/numpy,immerrr/numpy,jakirkham/numpy,embray/numpy,musically-ut/numpy,matthew-brett/numpy,Srisai85/numpy,ajdawson/numpy,anntzer/numpy,pyparallel/numpy,SiccarPoint/numpy,sonnyhu/numpy,pyparallel/numpy,argriffing/numpy,madphysicist/numpy,skymanaditya1/numpy,jorisvandenbossche/numpy,KaelChen/numpy,cowlicks/numpy,kirillzhuravlev/numpy,WarrenWeckesser/numpy,njase/numpy,numpy/numpy,sonnyhu/numpy,ViralLeadership/numpy,MaPePeR/numpy,has2k1/numpy,b-carter/numpy,BabeNovelty/numpy,AustereCuriosity/numpy,ChristopherHogan/numpy,gfyoung/numpy,mhvk/numpy,dwf/numpy,trankmichael/numpy,rgommers/numpy,KaelChen/numpy,rhythmsosad/numpy,ajdawson/numpy,moreati/numpy,Anwesh43/numpy,sigma-random/numpy,stefanv/numpy,rudimeier/numpy,Linkid/numpy,ViralLeadership/numpy,behzadnouri/numpy,mwiebe/numpy,joferkington/numpy,jankoslavic/numpy,bringingheavendown/numpy,cjermain/numpy,kirillzhuravlev/numpy,jonathanunderwood/numpy,dimasad/numpy,cowlicks/numpy,ahaldane/numpy,nbeaver/numpy,sinhrks/numpy,skwbc/numpy,empeeu/numpy,numpy/numpy,ewmoore/numpy,ewmoore/numpy,ChristopherHogan/numpy,grlee77/numpy,leifdenby/numpy,simongibbons/numpy,pdebuyl/numpy,bmorris3/numpy,ContinuumIO/numpy,dato-code/numpy,MichaelAquilina/numpy,immerrr/numpy,argriffing/numpy,SunghanKim/numpy,SunghanKim/numpy,has2k1/numpy,WillieMaddox/numpy,ahaldane/numpy,jorisvandenbossche/numpy,maniteja123/numpy,charris/numpy,andsor/numpy,NextThought/pypy-numpy,tacaswell/numpy,rgommers/numpy,ajdawson/numpy,dimasad/numpy,chatcannon/numpy,BabeNovelty/numpy,mindw/numpy,pdebuyl/numpy,endolith/numpy,kirillzhuravlev/numpy,jakirkham/numpy,githubmlai/numpy,groutr/numpy,dwf/numpy,ahaldane/numpy,shoyer/numpy,pizzathief/numpy,yiakwy/numpy,shoyer/numpy,NextThought/pypy-numpy,astrofrog/numpy,madphysicist/numpy,ddasilva/numpy,tdsmith/numpy,stuarteberg/numpy,rherault-insa/numpy,Linkid/numpy,moreati/numpy,mwiebe/numpy,kirillzhuravlev/numpy,dwillmer/numpy,solarjoe/numpy,mortada/numpy,shoyer/numpy,GrimDerp/numpy,Yusa95/numpy,larsmans/numpy,ajdawson/numpy,dwf/numpy,gmcastil/numpy,MaPePeR/numpy,WarrenWeckesser/numpy,tacaswell/numpy,MichaelAquilina/numpy,pelson/numpy,sigma-random/numpy,ekalosak/numpy,AustereCuriosity/numpy,jschueller/numpy,immerrr/numpy,mattip/numpy,kiwifb/numpy,solarjoe/numpy,skwbc/numpy,charris/numpy,seberg/numpy,chatcannon/numpy,Eric89GXL/numpy,grlee77/numpy,cjermain/numpy,jakirkham/numpy,anntzer/numpy,behzadnouri/numpy,madphysicist/numpy,madphysicist/numpy,Srisai85/numpy,trankmichael/numpy,ewmoore/numpy,embray/numpy,matthew-brett/numpy,pbrod/numpy,behzadnouri/numpy,jonathanunderwood/numpy,SiccarPoint/numpy,astrofrog/numpy,hainm/numpy,brandon-rhodes/numpy,rudimeier/numpy,pelson/numpy,mindw/numpy,dch312/numpy,mhvk/numpy,jschueller/numpy,felipebetancur/numpy,GrimDerp/numpy,SunghanKim/numpy,sinhrks/numpy,KaelChen/numpy,astrofrog/numpy,ahaldane/numpy,sinhrks/numpy,dwf/numpy,chiffa/numpy,ChristopherHogan/numpy,WarrenWeckesser/numpy,mortada/numpy,bringingheavendown/numpy,mathdd/numpy,jschueller/numpy,felipebetancur/numpy,solarjoe/numpy,tdsmith/numpy,bertrand-l/numpy,pbrod/numpy,Anwesh43/numpy,tynn/numpy,cjermain/numpy,yiakwy/numpy,SiccarPoint/numpy,Yusa95/numpy,musically-ut/numpy,mathdd/numpy,Dapid/numpy,BMJHayward/numpy,joferkington/numpy,ogrisel/numpy,skymanaditya1/numpy,ekalosak/numpy,KaelChen/numpy,gfyoung/numpy,abalkin/numpy,Linkid/numpy,maniteja123/numpy,mingwpy/numpy,seberg/numpy,simongibbons/numpy,pelson/numpy,MichaelAquilina/numpy,GrimDerp/numpy,rmcgibbo/numpy,anntzer/numpy,pelson/numpy,dimasad/numpy,stefanv/numpy,mathdd/numpy,mindw/numpy,Anwesh43/numpy,embray/numpy,sinhrks/numpy,nguyentu1602/numpy,Yusa95/numpy,Eric89GXL/numpy,sigma-random/numpy,empeeu/numpy,mindw/numpy,stefanv/numpy,ChanderG/numpy,mortada/numpy,mhvk/numpy,mattip/numpy,NextThought/pypy-numpy,pdebuyl/numpy,ogrisel/numpy,CMartelLML/numpy,felipebetancur/numpy,MichaelAquilina/numpy,immerrr/numpy,skymanaditya1/numpy,cjermain/numpy,ChanderG/numpy,pyparallel/numpy,embray/numpy,bmorris3/numpy,groutr/numpy,GrimDerp/numpy,githubmlai/numpy,dwf/numpy,nbeaver/numpy,jonathanunderwood/numpy,abalkin/numpy,shoyer/numpy,rajathkumarmp/numpy,gmcastil/numpy,jakirkham/numpy,charris/numpy,chiffa/numpy,ssanderson/numpy,ddasilva/numpy,CMartelLML/numpy,simongibbons/numpy,larsmans/numpy,anntzer/numpy,drasmuss/numpy,mathdd/numpy,astrofrog/numpy,simongibbons/numpy,pbrod/numpy,stuarteberg/numpy,endolith/numpy,gmcastil/numpy,MaPePeR/numpy,rudimeier/numpy,madphysicist/numpy,jakirkham/numpy,matthew-brett/numpy,bertrand-l/numpy,grlee77/numpy,rhythmsosad/numpy,stuarteberg/numpy,pizzathief/numpy,cowlicks/numpy,mingwpy/numpy,jorisvandenbossche/numpy,brandon-rhodes/numpy,musically-ut/numpy,dato-code/numpy,brandon-rhodes/numpy,larsmans/numpy,endolith/numpy,MSeifert04/numpy,trankmichael/numpy,CMartelLML/numpy,maniteja123/numpy,ViralLeadership/numpy,rudimeier/numpy,b-carter/numpy,empeeu/numpy,ogrisel/numpy,GaZ3ll3/numpy,hainm/numpy,dato-code/numpy,ChristopherHogan/numpy,ogrisel/numpy,tdsmith/numpy,ewmoore/numpy,stuarteberg/numpy,pbrod/numpy,Eric89GXL/numpy,GaZ3ll3/numpy,andsor/numpy,pizzathief/numpy,tdsmith/numpy,rmcgibbo/numpy,ewmoore/numpy,ekalosak/numpy,rajathkumarmp/numpy,Anwesh43/numpy,stefanv/numpy,ESSS/numpy,dch312/numpy,hainm/numpy,Srisai85/numpy,ssanderson/numpy,dato-code/numpy,dch312/numpy,seberg/numpy,MSeifert04/numpy,BMJHayward/numpy,rajathkumarmp/numpy,GaZ3ll3/numpy,mhvk/numpy,endolith/numpy,AustereCuriosity/numpy,rmcgibbo/numpy,mattip/numpy,charris/numpy,jankoslavic/numpy,simongibbons/numpy,rhythmsosad/numpy,trankmichael/numpy,seberg/numpy,yiakwy/numpy,ogrisel/numpy,chatcannon/numpy,BabeNovelty/numpy,andsor/numpy,stefanv/numpy,rgommers/numpy,naritta/numpy,jorisvandenbossche/numpy,numpy/numpy,bertrand-l/numpy,joferkington/numpy,MSeifert04/numpy,has2k1/numpy,cowlicks/numpy,bringingheavendown/numpy,ekalosak/numpy,GaZ3ll3/numpy,larsmans/numpy,tynn/numpy,SunghanKim/numpy,naritta/numpy,ahaldane/numpy,ContinuumIO/numpy,Dapid/numpy,utke1/numpy,ChanderG/numpy,naritta/numpy,rhythmsosad/numpy,mingwpy/numpy,leifdenby/numpy,ddasilva/numpy,musically-ut/numpy,jorisvandenbossche/numpy,drasmuss/numpy,githubmlai/numpy,naritta/numpy,mortada/numpy,mwiebe/numpy,githubmlai/numpy,kiwifb/numpy,pizzathief/numpy,bmorris3/numpy,Srisai85/numpy,mhvk/numpy,grlee77/numpy,matthew-brett/numpy,skymanaditya1/numpy,mingwpy/numpy,dwillmer/numpy,ssanderson/numpy,skwbc/numpy,ESSS/numpy,pizzathief/numpy,yiakwy/numpy,gfyoung/numpy,chiffa/numpy,abalkin/numpy,MSeifert04/numpy,njase/numpy,joferkington/numpy,jankoslavic/numpy,sonnyhu/numpy,pbrod/numpy,andsor/numpy,NextThought/pypy-numpy,numpy/numpy,nguyentu1602/numpy,drasmuss/numpy,dwillmer/numpy,rajathkumarmp/numpy,ContinuumIO/numpy,nguyentu1602/numpy,groutr/numpy,dwillmer/numpy,astrofrog/numpy,Dapid/numpy,leifdenby/numpy,BabeNovelty/numpy,WarrenWeckesser/numpy,tacaswell/numpy,tynn/numpy,felipebetancur/numpy,brandon-rhodes/numpy,jschueller/numpy,ESSS/numpy,embray/numpy,utke1/numpy,nguyentu1602/numpy,sigma-random/numpy,shoyer/numpy,dch312/numpy,MaPePeR/numpy