- Renaming GetCompilations() and GetSourcePathList() to follow LLVM
  style.
- Updating docs to reflect name change.
- Also updating help text to not mention clang-check since this class
  can be used by any tool.

Reviewed By: Alexander Kornienko


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@170229 91177308-0d34-0410-b5e6-96231b3b80d8