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

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