debug: added new tvhtrace logging routine

Note: this can be compile switch disabled (./configure --disable-trace)

Note: to enable subsystem output use --trace X,Y,Z etc... (--trace all
will enable the lot).

Note: the only way to know what subsystems are valie is to read the code!

Note: --trace implies -d
debug: convert all TRACE code to new tvhtrace routine
dvr/epg: added some more debug (trace) to look at what might be going on
init: add trace options to start scripts