improve support for clang

As of now, we have a code that emulates the behavior of `gcc -wrapper` in case clang (or other compiler) is being used.

However the argument parsing logic of the emulation is horrible; it just strips `-o target` and assumes that the last argument is the name of the source file. It is evident that such approach will fail in certain cases, e.g. when `-Wl,` is used after specifying the source file, or, when more than one source files are used.

We need to implement a better option parser like the one found in ccache or dist-cc.