removed unnecessary double-quote symbol.
org author: legal90, pr#120

- 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

improved title consistency
- changed - into dots to save space

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

html: don't hardcode uppercase texts

_If_ we want uppercase then it should be done in css.

#227 Initial version of repository groups permissions system
- implemented none/read/write/admin permissions for groups
- wrote more tests for permissions, and new permissions groups
- a lot of code garden, splitted logic into proper models
- permissions on groups doesn't propagate yet to repositories
- deprecated some methods on api for managing permissions on
repositories for users, and users groups

implements #226 repo groups available by path
fixes #259 Groups with the same name but with different parent group