replace deprecated % operator by format
add UserValueError

which is raised when a value provided by a user is not valid
UserValueErro take 2 optionnaly arguments parameters which is a list of
Parameter and message
add getter for para name property

and has_ctrl which return True if a para has crtl
Merge branch 'develop' of https://github.com/mobyle2/mobyle2.lib into develop

Conflicts:
	mobyle/common/service.py