Provide test for upscale_perm

Based on the discussion in #50, this PR provides a test for the binary `upscale_perm`. It is implemented as a CTest and it should be easy to extend new tests to this framework. The test procedure is twofold:

* Add test that runs the binary and output the results to a file
* Next, compare the output from the previous test with a reference solution. This is done by the executable `bin/compare_upscaling_results`.

Further documentation is available in-source.