Pvs/devel

- Assertions should be made fatal as soon as the build and testsuite runs without assertion failures.
- The testcases are used in obuild-aldor, in a directory-per-testcase fashion, so that special build flags, rules, expected output files, etc. are all in a directory. There can potentially be one expected output per architecture (e.g. for the min$MachineInteger bug in issue #38) and one for compiler/interpreter (though this should be an exception).