Better Boolean handling and debug statement

[lucperkins]

Handling all Actions YAML inputs as strings seems quite brittle. Using getBooleanInput instead of plain old string-returning getInput seems like a wise move whenever true Booleans are in question.

I've also added a debugging statement for the full command being run to start the server.

[colemickens]

There's also ACTIONS_STEP_DEBUG which should enable core.isDebug which should get you a bit extra spew.