logging stuff

[Dave Camp <dave novell com>]

I just checked in some logging stuff.  The quick overview:

* Running beagled with --out will log to the console instead of the log
file.  This is done by the wrapper script when running from the beagled
directory.

* You can log using Logger.Log.Debug ("foo {0}", "bar") (in
Beagle.Util).  This writes to the default context.  You can also log in
a different context using Logger.Get ("context").Debug ("blah").  This
is so that high-spew modules can be controlled separately.  Right now
the mail driver ("mail"), lucene driver ("lucene"), and crawler
("crawler") have their own contexts.

* The available calls are Fatal, Error, Warn, Info, and Debug.  By
default, Fatal through Info are shown.

* You can enable Debug spew using BEAGLE_DEBUG=comma,separated,contexts.
You can add "all" to BEAGLE_DEBUG to turn on debug spew for all
contexts.  The default context can be turned on using "other".

-dave