[mythtv] More multiple tuner support.

[Isaac Richards]

I just comitted this to CVS.  The scheduler support is still simplistic, but 
I've used it to successfully record two shows simultaneously to mpeg4 
1GB/hour at 640x480 with no dropped frames on my XP 1800+.

If upgrading to the current CVS tree, you need to run the 0-5-to-0-6.sql 
script that's in the database/ subdir to update the database format.  You'll 
then need to run the 'setup' program in the setup/ subdir to perform the 
initial database configuration for your hardware.  The setup program's text 
only for the moment; I plan on making it graphical before the next release.

Caveats:
- The database format has changed quite a bit.  Things may still be broken.  
I've tested everything I can think of, but something may have slipped 
through.

- All data in the conflict resolution tables, and all timeslot/single time 
recordings have been reset.  Sorry, but that was necessary.

- The new database format also requires some initial setup before things will 
work.  I've written a little setup program (now resides in the setup/ dir 
under the top level) that works with xmltv's tv_grab_na to do the initial 
setup.  Patches/etc welcome for other areas/grabbers.

- Previously recorded shows will have their channel number printed wrong in 
the playback/delete dialog boxes.  I figure this is an extremely minor 
problem, though.

- The scheduler does not yet support the following: connecting one external 
source to two different tuner cards, or searching for the same channel on two 
different channel sources (like, nbc on your cable feed is X, and it's the 
exact same channel on Y on your satellite feed).

- I haven't gotten back to testing the scheduler with one tuner card defined, 
yet.  Everything _should_ work, as the new resolution code only gets 
triggered if more than one card is defined in the database.

- It does not properly switch the input on the tuner card to S-Video or 
composite on a recording.  Should be easy to do, I just haven't written that 
yet.

There have also been some random bugfixes that went in in the same checkin, 
and the EPG now works in 5 minute increments, so any weirdness with some 
shows not showing up properly should be fixed now (thanks to Andrew Bishop 
for that reworking of the epg).

Thor, I updated mythweb as well, but I'm less sure of my changes there than I 
am of the ones in the main program.  Everything _seems_ to work, though.

Anyway, the next thing I'm going to work on beyond fixing any bugs that turn 
up in this new code will be to have encode quality levels on a per-recording 
or per-capture card basis, and the ability to re-encode recordings.

If you can, please test this.  More people banging on things means fewer 
problems overall.

Isaac