Allows to use more than one runtime. Should fix #8887 and #10558.

Created a Java Oracle8 Dockerfile directory and moved all build_interop.sh to under template/.  Added java_oracle8 to the client matrix.

Features included in this merge:
- Added script to build and upload docker image for matrix test.
- Added script to create test cases and created go__master testcases based on it.
- Created dictionary for runtimes and gRPC releases for supported languages.
- Added go 1.7 and 1.8 Dockerfile/templates.

See tools/interop_matrix/README.md for details.

Now that gRPC_INSTALL is forced off if using bundled third-party
libraries, it no longer makes sense to set it OFF by default for MSVC.

However, we do want to set it OFF by default if gRPC is being built as a
subproject of another project.

If gRPC is not getting its (link-time) dependencies from the system, it
should not be attempting installation.

This reverts commit c019e057.