Toy now fits into the C spec.
Fixed#158
Addendum: MacOS test caught an error:
error: a function declaration without a prototype is deprecated in all versions of C
That took 3 attempts to fix correctly.
Addendum: 'No new line at the end of file' are you shitting me?
Getting the array's length is still not available yet, so I'm not
marking arrays as done - but everything that is there is tested.
I've also tweaked the assert output callbacks to also print 'assert failure'.