Add engine tests for Mono

This PR adds the same engine script tests for Mono that are testing the Roslyn Engine.

This fixes #663 (at least partly)

Two things purposely left out to keep this PR cleaner and are part of other issues.
* Mono Engine does not throw CompileException and needs to be implemented.  Currently the <Code>ConsoleReportWriter</code> is displaying but "swallowing" the exceptions.  This issue is more connected to #664.
* Mono Engine does not support IsCompleteSubmission and therefore has no tests around that feature.  The engine tests around this should be included in the PR that fixes #665.