Allows the including of <assert.h>.
See script directory for method. The script to run in the top level MaxScale directory is called maxscale-uncrustify.sh, which uses another script, list-src, from the same directory (so you need to set your PATH). The uncrustify version was 0.66.
The test was not very clear about what it does. Added comments to clarify what is done and why. Also fixed a typo.
Added test case that reproduces the problem and verifies that it is fixed.
