DOC: Update testing section of README.
DOC: Update testing section of README.

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