[mythtv] scheduling and mythweb

[Chris Petersen]

> If Qt and MySQL are happy with all zeros, the scheduler should be OK
> with it too.  If it works, I'll change the mythtv code to match.

all zeros doesn't seem to do anything.  And setting to a fixed date has
issues because of the "unique" type index on oldrecorded - two shows
can't exist on the same channel with the same startting/endtime, they
just overwrite each other.

And there's no way to make the scheduler just ignore ANYTHING in
oldrecorded, like it used to?

-Chris