Clang Static Analyzer Integration

With `-enable-clang-static-analyzer` flag turned on, now it's able to painlessly invoke Clang Static Analyzer from OCLint, and the Clang Static Analyzer results will be integrated into OCLint report (with this pull request, only text reporter and HTML reporter could emit Clang Static Analyzer results).

However, running Clang Static Analyzer will *significantly* increase the total analysis time. So use it wisely.