Capabilities output format

Output of --capabilities parameter to command line has following syntax (stdout):

`Compressions:` `(...)` `Capturers:` `(...)` `Exit`

If -t parameter provided, UltraGrid tries to detect video signal and adjusts compress bitrates. otherwise, bitrate is set to zero. Syntax of tuples is following:

Comression:

(config_string;visual_quality[0-100];bitrate[bps];enc_latency[ms];enc_cpu_cores[units],encs_gpu[gflops];dec_latency[ms],dec_cpu_cores[units],dec_gpu[gflops])

Capturer:

(config_string:user_name)