[MediaPortal] Allow configuration of series recording settings.

## New features
Adds an addon-specific GUI dialog to configure series recording options.
The dialog is only enabled when the corresponding skin support files are found.
Currently supported skins:
* Ace
* Aeon Nox 5
* Aeon MQ5
* Amber
* Transparency
* Confluence

Note that this addition is rather large due to the dialog xml files for the skins.

## Bugfixes
Added also a bugfix for recording that are stored on an external server instead of the backend machine.