* loosen some test threshold mainly for integer types
* use relative error for floating points result
* avoid division by zero by following the comment
* fix the indentation
- removed tr1 usage (dropped in C++17)
- moved includes of vector/map/iostream/limits into ts.hpp
- require opencv_test + anonymous namespace (added compile check)
- fixed norm() usage (must be from cvtest::norm for checks) and other conflict functions
- added missing license headers
