XWIKI-10993: Integrate all themes from bootswatch in XWiki.
XWIKI-11347: Using an empty flamingo theme breaks the UI.
XWIKI-11353: Can't see separators on Menu with both skins
* Remove BR from empty LIs that are ment to be separators.
[cleanup] Updated document to the new xar format.
XE-1389: Welcome block is too hard to edit
- The welcome gadget now needs to display the Main.Welcome document in order for the sheet to be applied
- Added translation key
XWIKI-11354: Variable $theme.menuLinkColor takes #777 value, regardless of current theme.
[Misc] Minor startup performance improvement
[Misc] Add missing runtime scope
[Misc] Add missing runtime scope
[Misc] Add dep on the default implementation so that simply depending on the UI is enough to get everything
XWIKI-11343: Unable to get the XWiki Syntax Guide for XWiki Syntax 2.1 on certain locales.
XWIKI-11347: Using an empty flamingo theme breaks the UI.
XWIKI-10993: Integrate all themes from bootswatch in XWiki.
XWIKI-10993: Integrate all themes from bootswatch in XWiki.

* Add some values in the Flamingo Theme object to have a nice preview in the space webhome
XWIKI-11357: It's possible to loose external images files from an office preview when several preview of the same attachment are done with different parameters
XWIKI-11359: Cannot find users with accents in their name
* Set the default language when creating users.
* Improve the French analyzer
Merge branch 'master' of github.com:xwiki/xwiki-platform into feature-tree