Summary: Modify WhiteBoxAPI to use interface classes from test/testlibrary instead, add ClassFileInstaller to resolve the boot class path issue
Reviewed-by: ctornqvi, dsamersoff, coleenp, kvn

Summary: Add a few utility classes to test/testlibrary to support multi process testing in jtreg tests. Added a test case for one of the utility classes. Also reviewed by Vitaly Davidovich
Reviewed-by: brutisso, dholmes, vlivanov, nloodin, mgerdin