Split TestTemplateIntegerArgs test into two

Summary:
One of the tests there does not work with gcc, so I'm spinning that off into a separate test, so
that we can XFAIL it with more granularity.

I am also renaming the test to reflect the fact that it no longer tests only integer arguments.

Reviewers: clayborg

Subscribers: lldb-commits

Differential Revision: http://reviews.llvm.org/D21923

llvm-svn: 274505