Support Additional CTS Host Jars

Include another optional Makefile from the CTS project that
specifies additional JARs that the CTS host may need. This
will make it easier to create modules in the CTS project
that can be built for the host and device and shared between
the host and test cases.

The first such library will include annotations like
"RequiresFeature" and "SupportsProfile" that will be needed
to support multiple device profiles in CTS.

Another planned libraries could include defining the CTS
version number in a central spot and sharing code used to
probe for certain properties like the OpenGL version and
other system properties.

Can be checked in after this other change without causing
breakage: https://review.source.android.com/#change,16740

Change-Id: I3c488247b66522dc86277ab43198c34f790e0618