Added Github and SourceForge to list of socials.
Added StackOverflow to list of socials
Fix image tracker. Falsely showed link to index.php instead of piwik.php

Reported in: http://forum.piwik.org/read.php?2,101531
[ci skip]
Fix wrong tracking tag when piwik is hosted in a subdirectory.
Reported in http://forum.piwik.org/read.php?2,101531

[ci skip]
Restructure travis build.
This now builds PHP 5.3/5.4/5.5 x 3 Testsuites + all PHP x whole test (for code coverage)
Merge branch 'master' of https://github.com/piwik/piwik
Fix indent.
Fix path.
Bash script is weird - adding additional white space
.travis.yml
-> Only run full suite in PHP 5.4 with coverage
travis.sh
-> Remove code coverage from tests with specific suite
prepare.sh
-> Use/Install xmlstarlet to rewrite phpunit.xml
Merge branch 'master' into tests_fixture_refactor
Add one new fixture and converted 6 tests.
Converted last two tests.