Fix several crash-on-invalids when using template-ids that aren't
simple-template-ids (eg, 'operator+<int>') in weird places.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@196333 91177308-0d34-0410-b5e6-96231b3b80d8
Fix crash if a variable template specialization is used in a nested-name-specifier.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@196335 91177308-0d34-0410-b5e6-96231b3b80d8
clang-format-diff.py: Fix 'beintroduced' in help output

Also update docs to reflect recently changed -i inplace edit behaviour.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@196336 91177308-0d34-0410-b5e6-96231b3b80d8