* Added cl_khr_fp16 extension support for commonfns test (issue #142, commonfns)
* Added missing header due to presubmit check
* Corrected radians/degrees ulp calculations + cosmetic fixes
* Corrected presubmit code format
* Corrections related to code review
* Moved string format helper to test_common in separate header
* Added clang format for last commit
* Corrections related to code review
* Modified mix verification procedure for half type to only report max error
* Removed redundant condition for logging mix verification
* Corrected generator limits for half tests