Fix some glitches in the MSVCCompatibility document

- Fix the formatting of the "Exceptions and SEH" section.
- Make the "Complete" text for "Thread-safe initialization of local
  statics" green.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@236706 91177308-0d34-0410-b5e6-96231b3b80d8