Ffmpegoptions

ffmpeg and also libVLC support lots of settings to fine-tune communications with the camera, verbosity of debug output etc.
This enhancement adds an "Options" Field to the source tab of the monitor definition for ffmpeg and libVLC types.
![image](https://cloud.githubusercontent.com/assets/6896360/2878584/dac160b8-d45e-11e3-80de-46ebcc716039.png)
The options entered here are passed on the the libraries on opening
libVLC Example: ```--rtsp-tcp,--verbose=2``` use tcp transport mode for rtsp and increase verbosity to 2. debug messages show up if you run the monitor from the command line.
ffmpeg example:```rtsp_transport=tcp``` to use tcp transport mode instead of udp (it used to be possible to set this by appending ?tcp to the rtsp url, has been disabled in newer ffmpeg versions)
for both libraries, multiple options can be set separated by ";".
Does not support ffmpeg with LIBAVFORMAT_VERSION_INT < AV_VERSION_INT(53, 4, 0), option / parameter structure is different there.