merge 0.21.x branch into master
merge 0.21.x branch into master

hickford/cython,JelleZijlstra/cython,da-woods/cython,scoder/cython,fabianrost84/cython,slonik-az/cython,ABcDexter/cython,achernet/cython,marscher/cython,dahebolangkuan/cython,achernet/cython,roxyboy/cython,ChristopherHogan/cython,mrGeen/cython,JelleZijlstra/cython,marscher/cython,fperez/cython,achernet/cython,scoder/cython,fabianrost84/cython,madjar/cython,marscher/cython,fperez/cython,slonik-az/cython,mcanthony/cython,marscher/cython,JelleZijlstra/cython,acrispin/cython,madjar/cython,roxyboy/cython,fabianrost84/cython,achernet/cython,madjar/cython,da-woods/cython,hickford/cython,mcanthony/cython,dahebolangkuan/cython,roxyboy/cython,c-blake/cython,andreasvc/cython,ABcDexter/cython,ChristopherHogan/cython,roxyboy/cython,c-blake/cython,andreasvc/cython,acrispin/cython,andreasvc/cython,dahebolangkuan/cython,mcanthony/cython,JelleZijlstra/cython,da-woods/cython,scoder/cython,mrGeen/cython,encukou/cython,mrGeen/cython,andreasvc/cython,hickford/cython,fabianrost84/cython,c-blake/cython,c-blake/cython,encukou/cython,hhsprings/cython,cython/cython,encukou/cython,encukou/cython,cython/cython,madjar/cython,c-blake/cython,achernet/cython,fperez/cython,da-woods/cython,andreasvc/cython,roxyboy/cython,ABcDexter/cython,ABcDexter/cython,hickford/cython,acrispin/cython,dahebolangkuan/cython,mcanthony/cython,fperez/cython,encukou/cython,ABcDexter/cython,madjar/cython,slonik-az/cython,fperez/cython,hhsprings/cython,hickford/cython,acrispin/cython,mrGeen/cython,acrispin/cython,hhsprings/cython,mrGeen/cython,dahebolangkuan/cython,slonik-az/cython,scoder/cython,hhsprings/cython,cython/cython,slonik-az/cython,marscher/cython,hhsprings/cython,fabianrost84/cython,mcanthony/cython,JelleZijlstra/cython,ChristopherHogan/cython,cython/cython