Implemented rudimental search engine
Fixes to search engine

Changed the search parameter from POST to GET.
Also, adapted the Baggy theme.
Merge pull request #582 from mariroz/fix-session-livetime

fix of localhost cookie related to nginx binding to 0.0.0.0
Finished search engine function

Now searches also in title and in original url
Fix of #580 : Add some random for Windows hosts
Improvements for compatibility_test file

- gettext detection (not default on WAMP) ; part fix of #579
- added colors to make viewing what's wrong better and quicker
(green/orange/red)
- added a link to index.php if it's good
wallabag a link in wallabag now in default theme, issue #505