Iteration on default permissions
- added user groups default
- organized global permission form, and made it common for
users, and user groups
- form improvements and intructions

- Manage User’s Groups: create, delete, rename, add/remove users inside.
by user group admin.
In this case, a user's group can be owned by several people thru an owner user's group.

Some refactoring of naming, permission handling logic.
- remove some code duplicity as well as inconsistent naming

fixed sort of permissions summary it's now perm+name
unified permissions summary for users and user groups

user group: sort lists of current and available members by username

It was hard to navigate lists with 200 users in "random" (user_id?) order.

sort permission lists by (repository) name

This also exhibits too much code in templates and code/template duplication.

improved title consistency
- changed - into dots to save space

further cleanup of UsersGroup

Renaming some names ... but trying not to change API or database scheme.

Group management delegation:
this allows users to become an admin of groups
a group admin can manage a group, change it's name
or permissions. A group admin can create child group
only within a group he is an admin off.

Top-level group can be only created by super admins

RhodeCode now has a option to explicitly set forking permissions. ref #508
- changed the way permissons on users groups behave. Now explicit set on user
is more important than permission set on users group

fixed inline comment indicator.
- templates cleanup

Fixed permissions for users groups, group can have create repo permission now.
Some code refactor + pep8ify

Fixed #161 form saves the create repository permission.
routing update for users to support second form posting.
models updates

#56 implemented users groups editing,
fixed sqlalchemy relation function into relationship (according to 0.6)