Make preview possible if session_enabled = 0
Check for additional valid MIME types for zip files.

Wondered why my local transport packages aren't valid zip-files for MODx until I found out that Firefox is uploading them with MIME type 'application/x-zip-compressed'.
Ignore case on MIME type check
Fixing Preview from resource tree
Fix html entity encoded param ampersand
Make preview possible if session_enabled = 0

* origin/pr/11204:
  Fix html entity encoded param ampersand
  Fixing Preview from resource tree
  Make preview possible if session_enabled = 0
Translated new phrases to German
Fix Incorrect urlAbsolute Path

Closes modxcms/revolution#11291
Translated new phrases to German

* origin/pr/11289:
  Translated new phrases to German
Check for additional valid MIME types for zip files during package upload

* origin/pr/11274:
  Ignore case on MIME type check
  Check for additional valid MIME types for zip files.
Fix Incorrect urlAbsolute Path

* origin/pr/11292:
  Fix Incorrect urlAbsolute Path
Update dashboard CSS
Rebasing + generating index.css
More width for dashboard widgets when the tree is collapsed

* origin/pr/11294:
  Rebasing + generating index.css
  Update dashboard CSS