Analysis: Add support for MS specific printf format specifiers

Summary: Adds support for %I, %I32 and %I64.

Reviewers: hans, jordan_rose, rnk, majnemer

Reviewed By: majnemer

CC: cfe-commits, cdavis5x

Differential Revision: http://llvm-reviews.chandlerc.com/D1456

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@188937 91177308-0d34-0410-b5e6-96231b3b80d8