XWIKI-10808: Missing doc authors in Flamingo skin

* Typo: extra quote
XWIKI-10577: Move wiki.css selectors to colibri.css

* Remove call to a-non-existing-anymore-file in Flamingo
XCOMMONS-628: Upgrade Jasmin Maven plugin to 1.3.1.5
XWIKI-10711: Be able to have a Header in Flamingo

* Adding a new variable in layoutvars.vm called $displayPageHeader, default in Flamingo to false, that if set mimics the Colibri header behaviour by displaying the logo and the banner taken from ColorThemes
XWIKI-10827: Browser does not scroll to extradoc panes when the corresponding shortcuts are fired.
XE-1404: Switch to Flamingo Skin by default.

* Better comment.
XWIKI-10826: Impossible to run 2 instances of XWiki on same Tomcat instance because of Solr
- Using only xwiki.properties to configure Solr's home directory, ignoring any system property or any environment/JNDI entry.
- Fixed tests
XWIKI-5347: Upgrade to VelocityTools 2.0
- WebappLoader got moved to a new package. Using the new location to avoid deprecation warnings in the console logs.
XWIKI-10711: Be able to have a Header in Flamingo

* Use companylogo.vm instead
[Misc] Revert changes done by sdumitriu. The relativePath should not be set to not cause problems with Jenkins. BTW I couldn't reproduce the build warning problem that Sergiu fixed in his commit (would be interested to know more about it).
[Misc] Force Maven to use its repositories to resolve parent POM for top level modules. This is to prevent any error such as having a pom.xml file located in a directory above the top level modules for example.
XWIKI-10828: Speed up XWiki instance starting in functional tests
XWIKI-8631: Stop XWiki process in functional tests if XWiki is already started when the test starts
[Misc] Fixed wrong functional tests which was starting XWiki twice...
XWIKI-10829: Executing the import mojo after the package mojo in the same reactor causes the build to fail

Fixed.