bug #4617: install rack < 2.0.0 for ruby < 2.2.0
bug #4617: install rack < 2.0.0 for ruby < 2.2.0

(cherry picked from commit ecf6c40dded8ba61acc6e403b2a0f5626102e339)

ohamada/one,goberle/one,baby-gnu/one,unistra/one,goberle/one,juanmont/one,hsanjuan/one,hsanjuan/one,hsanjuan/one,alvarosimon/one,baby-gnu/one,alvarosimon/one,ohamada/one,OpenNebula/one,juanmont/one,alvarosimon/one,OpenNebula/one,abelCoronado93/one,OpenNebula/one,OpenNebula/one,OpenNebula/one,abelCoronado93/one,ohamada/one,unistra/one,juanmont/one,atodorov-storpool/one,unistra/one,atodorov-storpool/one,atodorov-storpool/one,atodorov-storpool/one,atodorov-storpool/one,baby-gnu/one,baby-gnu/one,goberle/one,abelCoronado93/one,hsanjuan/one,abelCoronado93/one,juanmont/one,ohamada/one,abelCoronado93/one,alvarosimon/one,hsanjuan/one,ohamada/one,hsanjuan/one,juanmont/one,unistra/one,hsanjuan/one,abelCoronado93/one,abelCoronado93/one,goberle/one,OpenNebula/one,abelCoronado93/one,juanmont/one,unistra/one,baby-gnu/one,unistra/one,goberle/one,alvarosimon/one,unistra/one,atodorov-storpool/one,goberle/one,alvarosimon/one,ohamada/one,goberle/one,alvarosimon/one,atodorov-storpool/one,juanmont/one,ohamada/one,OpenNebula/one,baby-gnu/one,juanmont/one,unistra/one,OpenNebula/one,atodorov-storpool/one,alvarosimon/one,ohamada/one,hsanjuan/one,OpenNebula/one,baby-gnu/one,goberle/one,baby-gnu/one,juanmont/one,atodorov-storpool/one