use categories on messages
There are too many debug messages when --debug is enabled, and,
from time to time, we add more as needed to solve bugs.
That makes the log too long, making harder to debug an specific
issue, specially due to too noisy logs like EPG.
So, let's organize the messages on category groups, with will
make easier to enable/disable them individually via command
line arguments.
With this change, it is now possible for example to enable debug
but disabling all EPG debug messages with:
QT_LOGGING_RULES="kaffeine.epg.debug=false" kaffeine --dumpdvb --debug
To enable debug for DVB device parameters sent via libdvbv5:
QT_LOGGING_RULES="kaffeine.dev.debug=true" src/kaffeine
To enable other DVB-related debug messages:
QT_LOGGING_RULES="kaffeine.dvb.debug=true" kaffeine
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>