gitignore line ending problems
implemented change of container reference for rolegroups and roletypes

see bug #20
added containter role to rolegroup and rolemodel
fixes bug #20

RoleTypes and RoleGroups inherit from Node which holds a location
coordinate. This determines the location in the model and needs to be
adapted when moving the respective model around (e.g., alter its
parent). This was not reflected in the commits before.
reformatting