Run VICE-based tests in CI

[jdpage]

PR #59 introduced a harness for testing gold-syntax programs by running them under VICE. Currently, these cannot be run under either of our CI setups; it currently hangs under Travis' Ubuntu Trusty, which ships an old version of VICE (without ROMs, though that's easy to fix), and AppVeyor uses Windows, which is unsupported (see #60).

It doesn't really matter which CI system the tests get run under. If fixing #60 gets us AppVeyor support, that's cool, though we won't get coverage. I'm not really sure what the best way to get it working under Travis is, though the two options that stand out are getting VICE 3.2 binaries into the build environment, or modifying the driver to work with VICE 2.4.