[Clang-Tidy] Preserve Message, FileOffset, FilePath in Clang-Tidy YAML output

Summary:
To get properly integration Clang-Tidy with CLion IDE, next things were implemented:
1) Preserve `Message`, `FileOffset`, `FilePath` in the clang-tidy output.
2) Export all diagnostics, not just the ones with fixes
3) Test-cases

Reviewers: klimek, ilya-biryukov, alexfh

Reviewed By: alexfh

Subscribers: alexfh, JDevlieghere, mgorny, xazax.hun, cfe-commits, klimek

Tags: #clang-tools-extra

Patch by Vladimir Plyashkun!

Differential Revision: https://reviews.llvm.org/D34404

llvm-svn: 308014