gallery 5.x-2.1

This is a bugfix release for the 5.x-2.x series of gallery module.

Release notes for this series including a list of features and changes in comparison to earlier versions can be found in the initial release notes (5.x-2.0) of the 5.x-2.x series.

Changes from 5.x-2.0 to 5.x-2.1

Gallery
- bugfix: G2 filter appears as text when user has no permission (#195106)
- bugfix: move admin sidebar doesnt work for plugins page (#195879)
- bugfix: broken breadcrumbs for dynamic albums (#207986)
- bugfix: bad css ids for install table (#207843)
- bugfix: install still checks for gsitemap module (#208872)
- bugfix: empty title not handled properly in status reports
- bugfix: advanced search form broken
- bugfix: final stage of integration (user sync) fails if gallery_menu module is enabled (#217090)
- bugfix: gallery pages not updated if page cache is enabled (#216775)
- task: specificItem needed to get album thumbnail instead of album content (workaround option for #196149)
- task: unify head html output (in _search.inc)
- task: make G2 filter tag case-insensitive
- task: add request details to reports
- task: additional notice if url rewrite needs configuration
- task: backport cleanup stuff from D6
- feature: improved formatting of debug output