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.

compare: swap org and other when they refer to different repos, ie are pull request style

Pull requests will have a different from/to description - but in a consistent
and slightly better way that can be improved later.

A pull request diff is empathic: "How will this look for the peer I'm proposing to" style.

compare: rename optional compare_url parameter repo to other_repo

At the same time it is placed before other_ref_type and other_ref. Just to keep
a logical flow and (a new) consistency that will help the next refactoring.

new tooltip implementation
- added lazy loading of changeset tooltips for journal data

Added h.tooltip to all places that tooltip_title is used.
- improved escaping of < and > inside tooltips