Update documentation for all CERT checks that correspond to a recommendation.

CERT removed their C++ secure coding recommendations from public view and so the links within that documentation are stale. This updates various pieces of documentation to make this more clear, and to help add substance where our docs deferred to CERT's wiki.

git-svn-id: https://llvm.org/svn/llvm-project/clang-tools-extra/trunk@366687 91177308-0d34-0410-b5e6-96231b3b80d8
4 files changed