Partial revert of "mpegts: add PMT monitoring option"

- removed the pmtmon option
- kept the PMT table handling for given service
Optimize the PIDs filtering

- only used CA PIDs are opened
- all PMT PIDs are opened only at the initial scan

The SAT>IP boxes have limited count of PIDs filters (and probably some
linuxdvb hardware too), so try to use these resources better.
Show the CAIDs in hex in the service info dialog plus add the provider number
Merge pull request #377 from perexg/pid-filter

Optimize the PIDs filtering
Merge pull request #379 from perexg/service-info-caid

Show the CAIDs in hex in the service info dialog plus add the provider
Add transcoding via filter scripts to http streaming
Read optional transcoder.mime file to determine a custom mime-type