Support C++ iterators in for..in loops.
Support C++ iterators in for..in loops.

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