Merge pull request #36 from unknownbrackets/cpu

Add test for writing to $0
Fixed $k0 test
Add basic functionality to specify the sdk ver.
Add a feature to run and compare multiple versions.
Add a list of different tests at the end.
Recompile a bunch of tests with the sdkver opt.

Also fix the __testfinish.txt issue in emulator mode.
Don't use printf() in semaphores.

Sudden midnight thread switching?  Unsightly missing newlines?
schedf (TM) brand schedf (TM) has you covered.  Just apply generously.
Timeouts were dying, oops.