Fixes numerous issues.

[coccyx]

• Closes Handle unknown control character errors more gracefully #3: Should handle unknown characters in dashboard event output more
  gracefully.
• Closes Returns last N events matching filter #8: Now returns event count after filtering, except for with JS
  expressions.
• Closes Q should exit scope dash #9: Q now exits dash.
• Closes Help should have consistent capitalization #12: Help should now have consistent capitalization.
• Closes scope run needs more examples #7: Scope run now has more examples.
• Closes Commands which error should potentially print help #4: Commands which fail validation now print help.
• Closes Deal better failed command executions #1: Failed executions now prompt to clean empty session.
• Closes log watch regex should be smarter to only pick up log directories and files containing log in the filename #19: Log Regex is now smarter about picking up log directories or
  files.
• Closes scope metrics -c with no metrics fails silently #17: scope metrics -c no longer fails silently.
• Closed Compact scope proc single value metrics #23: rearranges scope dash to be more compact.

[coccyx]

This has reverted @jrcheli commit and we'll need to resolve how to handle this to make tests succeed. Will chat Monday.

[coccyx]

@iapaddler can you review? We should be ready to merge. I'm working on getting tests running better/more successfully in another branch.