First step in two-part process to rename directories to kallithea.
This first step is to change all references in the files where they refer
to the old directory name.

Imported some of the GPLv3'd changes from RhodeCode v2.2.5.

This imports changes between changesets 21af6c4eab3d and 6177597791c2 in
RhodeCode's original repository, including only changes to Python files and HTML.

RhodeCode clearly licensed its changes to these files under GPLv3
in their /LICENSE file, which states the following:
The Python code and integrated HTML are licensed under the GPLv3 license.

(See:
https://code.rhodecode.com/rhodecode/files/v2.2.5/LICENSE
or
http://web.archive.org/web/20140512193334/https://code.rhodecode.com/rhodecode/files/f3b123159901f15426d18e3dc395e8369f70ebe0/LICENSE
for an online copy of that LICENSE file)

Conservancy reviewed these changes and confirmed that they can be licensed as
a whole to the Kallithea project under GPLv3-only.

While some of the contents committed herein are clearly licensed
GPLv3-or-later, on the whole we must assume the are GPLv3-only, since the
statement above from RhodeCode indicates that they intend GPLv3-only as their
license, per GPLv3§14 and other relevant sections of GPLv3.

Implemented simple gist functionality ref #530.

- creation of public/private gists with given lifetime
- rhodecode-gist CLI for quick gist creation

- 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

#749 and #516 Removed dupliciting of repo settings for rhodecode admins and repo admins
- repo admin now is allowed the same set of operations as the rhodecode admin
- single logic for forms/validations/permissions
- fixes #805 update external repo via webinterface
-

follow Python conventions for boolean values

True and False might be singletons and the "default" values for "boolean"
expressions, but "all" values in Python has a boolean value and should be
evaluated as such. Checking with 'is True' and 'is False' is thus confusing,
error prone and unnessarily complex.

If we anywhere rely and nullable boolean fields from the database layer and
don't want the null value to be treated as False then we should check
explicitly for null with 'is None'.

Pass in old groups data to CanWriteToGroup validator for later skipping group checks.
This will be a part of refactoring done to do user permissions changes without messing with main
repo form data

Pass in old groups data to CanWriteToGroup validator for later skipping group checks.
This will be a part of refactoring done to do user permissions changes without messing with main
repo form data

further cleanup of UsersGroup

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

move permission check of write access to repo groups inside a form.
- it's runned via create/edit/fork forms
- in case we have disabled repo creation, it will check root location write access for people that are not super admins, or have explicity create repo permission
- in case there's a group value passed to form, it checks just admin or write access

repository extra fields implementation
- verion bump to 1.6
- migrations

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

Added UserIpMap interface for allowed IP addresses and IP restriction access
ref #264 IP restriction for users and user groups

Fixed some issues with edit form
- unified code (but still a lot of duplicated code left over)
- fixed forms
- fixed validators

Fixed #585, checks for status of revision where to strict, and made opening pull request with those revision impossible due to previosly set status.
Checks now are made also for the repository.

Implemented permissions for writing to repo
groups. Now only write access to group allows to create a repostiory
within that group

Permissions on group can be set in recursive mode setting defined permission to all children
- more explicit permissions
- fixes for empty values in permission form

Changed v.Set validation into our own that actually raises exceptions on missing values.
Added NotReviewedRevisions validator

Added optional flag to make_ui to not clean sqlalchemy Session.
Don't clear sqlalchemy session when using make_ui in admin repo form

added more validations when opening pull request
- fixed issues with moving tags/bookmarks/branches after opened pull-request
- no longer possible to open a pull-request without changesets
- title is required
- validate reviewers and revisions

Fixed validators for remote repos
- use proper httppeer repo for mercurial 2.3
- validate git repos for remote auth
- docs updates

allow cloning with hgsubversion (reimplementing pull request 46)

sadly I get a exception from hg-git when doing the same for git+http URLs
so I did not implement it for hg-git