DOC: add a brief note on "Protocols for methods" to NEP 18
DOC: add a brief note on "Protocols for methods" to NEP 18

shoyer/numpy,MSeifert04/numpy,pbrod/numpy,mattip/numpy,charris/numpy,madphysicist/numpy,jakirkham/numpy,seberg/numpy,gfyoung/numpy,mattip/numpy,rgommers/numpy,grlee77/numpy,mattip/numpy,WarrenWeckesser/numpy,pizzathief/numpy,ahaldane/numpy,madphysicist/numpy,shoyer/numpy,simongibbons/numpy,jorisvandenbossche/numpy,pizzathief/numpy,MSeifert04/numpy,pbrod/numpy,WarrenWeckesser/numpy,ahaldane/numpy,jorisvandenbossche/numpy,endolith/numpy,pbrod/numpy,pdebuyl/numpy,WarrenWeckesser/numpy,anntzer/numpy,numpy/numpy,shoyer/numpy,ahaldane/numpy,charris/numpy,rgommers/numpy,MSeifert04/numpy,jorisvandenbossche/numpy,pdebuyl/numpy,grlee77/numpy,seberg/numpy,pizzathief/numpy,charris/numpy,WarrenWeckesser/numpy,jorisvandenbossche/numpy,ahaldane/numpy,abalkin/numpy,simongibbons/numpy,ahaldane/numpy,rgommers/numpy,pbrod/numpy,mhvk/numpy,MSeifert04/numpy,endolith/numpy,numpy/numpy,seberg/numpy,mhvk/numpy,numpy/numpy,mhvk/numpy,simongibbons/numpy,rgommers/numpy,pdebuyl/numpy,madphysicist/numpy,mhvk/numpy,shoyer/numpy,grlee77/numpy,abalkin/numpy,jakirkham/numpy,abalkin/numpy,mattip/numpy,numpy/numpy,MSeifert04/numpy,jakirkham/numpy,grlee77/numpy,grlee77/numpy,pizzathief/numpy,pdebuyl/numpy,jakirkham/numpy,jorisvandenbossche/numpy,charris/numpy,anntzer/numpy,gfyoung/numpy,mhvk/numpy,shoyer/numpy,pizzathief/numpy,anntzer/numpy,madphysicist/numpy,jakirkham/numpy,simongibbons/numpy,WarrenWeckesser/numpy,gfyoung/numpy,madphysicist/numpy,simongibbons/numpy,pbrod/numpy,anntzer/numpy,endolith/numpy,endolith/numpy,seberg/numpy