Run Closure Compiler OTI and NTI in parallel.
Run Closure Compiler OTI and NTI in parallel.

This should reduce test execution time on multi core system by running the single threaded compiler in parallel.

alexeagle/tsickle,drjanitor/tsickle,angular/tsickle,drjanitor/tsickle,drjanitor/tsickle,angular/tsickle,drjanitor/tsickle,alexeagle/tsickle,alexeagle/tsickle