Moving junit out of core.jar and into core-junit.jar.

Previously it wasn't possible to start a dalvikvm without
a copy of JUnit on the boot class path.

Change-Id: I52f924207efe0a115e69616111807c6738d1a17f
https://android-git.corp.google.com/g/#change,50609
https://android-git.corp.google.com/g/#change,50610
https://android-git.corp.google.com/g/#change,50611
19 files changed