Log Message:
Update contao31 to 3.1.3.

Version 3.1.3 (2013-09-24)
--------------------------

### Fixed
Do not redirect to protected pages after logout (see #6210).

### Fixed
Consider the additional arguments in `Frontend::jumpToOrReload()` (see #5734).

### Fixed
Prevent article aliases from using reserved names (see #6066).

### Fixed
Correctly update the RSS feeds if a news item or event changes (see #6102).

### Fixed
Correctly link to news and calendar feeds via insert tag (see #6164).

### Fixed
Make the CSS ID available in the custom navigation module (see #6129).

### Fixed
Do not cache the "toggle_view" insert tag (see #6172).

### Fixed
Unset the primary key if a model is deleted (see #6162).

### Fixed
Support `tel:` and `sms:` upon IDNA conversion (see #6148).

### Fixed
Apply the width and height to the audio player as well (see #6114).

### Fixed
Do not exit after a template has been output (see #5570).

### Changed
Drop the database query cache (see #6070). This renders `executeUncached()` and
`executeCached()` deprecated. Use `execute()` instead.

### Fixed
Handle all possible errors when uploading files (see #5934).