Sabbus Windows fix

All,

included is the updated patch for the build file.  I'd like to be able to commit this soon, as it fixes the command-line length limitations on windows.  I wanted to bring up a few points:

• This patch completely removes the need for scalacfork ant task.  The scalac ant task was updated earlier with forking ability and fixed for windows command-line limitations.  I think maintaining one task would be far better than two.
• Currently there are two places where JVM arguments are supplied to the scala build process.  One is the "scalacfork.jvmargs" ant property, and the other is "ANT_OPTS" environment variable.  I'd like to try to unify these at some point, so there is no confusion on how/where to update these values.
• Building strap is currently pulling in the pack scala ant tasks.  I'm not positive ant is correctly isolating the classpath for the locker ant tasks vs. the strap classpaths.  I ran test.stability and things were fine, but I'm not sure how to ensure that the non-forked scalac is actaully different when used in strap (I'm aliasing the task when I import, so, AFAICT things are correct, but my ANT classloading foo is very very rusty.  Maven OTOH...)

Anyway, I was hoping I could get some other eyes looking at this, but if I don't receive any complaints, I plan to commit soon (before it drops off my radar again).  I'm not sure if any of these decisions would cause any disagreement, but please let me know if I'm doing something off-axis here.  I could really use this fix for building in windows!!!

-Josh