DOC: document NEP-18 overrides in release notes
DOC: document NEP-18 overrides in release notes

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