Add a matcher for SubstNonTypeTemplateParmExpr.

Reviewers: klimek, djasper

Reviewed By: djasper

Subscribers: klimek, aemerson, cfe-commits

Differential Revision: http://reviews.llvm.org/D4327

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@212001 91177308-0d34-0410-b5e6-96231b3b80d8