Log Message:
Update contao42 to 4.2.5.

### 4.2.5 (2016-10-27)

 * Unlock members after password change (see contao/core#8545).
 * Register an alias for the language fallback page model (see
   contao/core#8544).
 * Correctly calculate the maximum length of tl_files.name (see
   contao/core#8536).
 * Correctly add the headline if a content element is versionized (see
   contao/core#8502).
 * Optimize the DCA sorting filter for date fields (see contao/core#8485).
 * Do not show version entries of deleted files (see contao/core#8480).
 * Redirect the empty URL depending on language and alias name (see
   contao/core#8498).
 * Apply `specialchars()` to widget attributes (see contao/core#8505).
 * Queue the requests when rebuilding the search index (see contao/core#8449).
 * Correctly determine the form field names in the file manager (see #600).
 * Correctly show the maximum file size in the form upload widget (see #595).
 * Correctly encode e-mail addresses in the text element (see #594).
 * Do not parse front end templates twice (see #599).
 * Correctly set host and scheme in the URL generator (see #592).
 * Correctly reload the page and file trees in "edit multiple" mode.
 * Correctly normalize the paths in the symlink command.