BENCH: Split bench_function_base.Sort into Sort and SortWorst.
BENCH: Split bench_function_base.Sort into Sort and SortWorst.

SortWorst houses the worst-case setup code and the time_sort_worst method.

Everything else remains in Sort.

Done in response to issue #11875

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