_jelly_ command-line tool should set non-zero exit status for compilations with errors

[chrysaora-achlyos]

Is your feature request related to a problem? Please describe.

jelly command always exits with status 0 if the Compile command is run on source code, so any script (bash or otherwise) that want to call the jelly command must parse stdout for the the existence of compilation errors

Describe the solution you'd like

Instead of just printing "Found (EventReporter.shared.events.count) errors" to stdout, the command-line tool could throw an error or otherwise exit with non-zero status