BUG: Fix #4476 by adding datetime64 and timedelta64 types
BUG: Fix #4476 by adding datetime64 and timedelta64 types

This commit fixes bug #4476 by adding the codes for the datetime64 and
timedelta64 types to the `default_filler` dictionary in numpy.ma.core,
used by `default_fill_value`.  Also adapt checking in the
`default_fill_value` to include code for timedelta64, not only datetime64.

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