TST: stats: add axis=None tests
TST: stats: add axis=None tests

zerothi/scipy,vigna/scipy,anntzer/scipy,perimosocordiae/scipy,zerothi/scipy,Stefan-Endres/scipy,tylerjereddy/scipy,scipy/scipy,vigna/scipy,tylerjereddy/scipy,endolith/scipy,WarrenWeckesser/scipy,grlee77/scipy,ilayn/scipy,Stefan-Endres/scipy,rgommers/scipy,tylerjereddy/scipy,ilayn/scipy,Stefan-Endres/scipy,zerothi/scipy,matthew-brett/scipy,mdhaber/scipy,endolith/scipy,WarrenWeckesser/scipy,andyfaff/scipy,rgommers/scipy,matthew-brett/scipy,WarrenWeckesser/scipy,perimosocordiae/scipy,perimosocordiae/scipy,zerothi/scipy,WarrenWeckesser/scipy,ilayn/scipy,ilayn/scipy,endolith/scipy,ilayn/scipy,WarrenWeckesser/scipy,andyfaff/scipy,scipy/scipy,vigna/scipy,mdhaber/scipy,perimosocordiae/scipy,vigna/scipy,tylerjereddy/scipy,anntzer/scipy,anntzer/scipy,scipy/scipy,vigna/scipy,zerothi/scipy,rgommers/scipy,scipy/scipy,perimosocordiae/scipy,Stefan-Endres/scipy,endolith/scipy,perimosocordiae/scipy,matthew-brett/scipy,grlee77/scipy,Stefan-Endres/scipy,matthew-brett/scipy,Stefan-Endres/scipy,grlee77/scipy,matthew-brett/scipy,rgommers/scipy,mdhaber/scipy,andyfaff/scipy,rgommers/scipy,WarrenWeckesser/scipy,scipy/scipy,mdhaber/scipy,andyfaff/scipy,andyfaff/scipy,anntzer/scipy,grlee77/scipy,ilayn/scipy,mdhaber/scipy,endolith/scipy,grlee77/scipy,scipy/scipy,anntzer/scipy,endolith/scipy,andyfaff/scipy,mdhaber/scipy,anntzer/scipy,zerothi/scipy,tylerjereddy/scipy