[pp-trace] Delete -ignore and add a new option -callbacks

Summary:
-ignore specifies a list of PP callbacks to ignore. It cannot express a
whitelist, which may be more useful than a blacklist.
Add a new option -callbacks to replace it.

-ignore= (default) => -callbacks='*' (default)
-ignore=FileChanged,FileSkipped => -callbacks='*,-FileChanged,-FileSkipped'

-callbacks='Macro*' : print only MacroDefined,MacroExpands,MacroUndefined,...

Reviewers: juliehockett, aaron.ballman, alexfh, ioeric

Reviewed By: aaron.ballman

Subscribers: nemanjai, kbarton, jsji, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D59296

llvm-svn: 356366