Remove mocha-runner and just run mocha directly

Upgrade should.js to more recent version
Rebuild binaries before testing, tests are currently destructive
Separate module path generation from loading

Also cleans up some styling, removes excess coments,
uses a named stub, and switch to single-quotes for strings.
Clean up version mapping

Tightens up the mapping so that v0.100.0 doesn't match as a v0.10 release
Clean up tests, fill in some gaps

 * Use generated paths in load tests
 * Ensure paths start with ./ so that require() treats them as relative paths
 * Tests for OS and arch mapping
Merge branch 'feature/rmg-ci-friendly'

Improves compatibility with StrongLoop's CI and improves overall
testability.

Closes #6