0.5.0

breaking change.

-feat: leave nightly and use only stable.
Replace min_specialization unstable feature by dep trait_gen.
-feat: bring trait PromtableDisplay
-feat: change api of trait Promptable
-feat: macro implement for trait Promptable, do not create new traits.
-feat: generic implementation of Promptable<&str> for Vec
-feat: use of tuples to pass parameters to function inside macro.
-feat: big rewrite, organize and clean code, specially in macro.
-feat: new field attributs: short_display
-feat: update examples
-feat: update test
-feat: update doc
-feat: update README