MyChat Scripts Engine: user rights management

Managing MyChat user rights; working with roles (rights group).

mGetRoleIDByName	get a numeric identifier of a group by its name;
mGetRoleNameByID	get a name of a user rights group by its numeric ID;
mGetUserRoleID	get a user rights group identifier by his UIN;
mGetUserRoleName	get a name of a user rights group by his UIN;
mSetUserRoleID	set a rights group for a user.