Killing coffee process does not kill child node process

[svicalifornia]

See remy/nodemon#195

When running coffee --nodejs ..., a node child process is created.

Killing/restarting the coffee process does not kill the node process and can continue tying up resources that the new process needs to access. For example, if node was started with --debug, then it will keep using port 5858, preventing the newly spawned node process from opening that port.

Workaround is to abandon the coffee command and use:

node --debug ./node_modules/.bin/coffee path/to/script.coffee

However, it seems the coffee command is essentially useless when launching node and working with automated restart workflows.

Proposed solution: coffee should handle SIGINT and SIGTERM and kill any child processes it has started.

[GeoffreyBooth]

While a fix for this would be welcomed as a PR, the coffee command is not meant to replace the Node runtime. Its primary use is compiling CoffeeScript, and other functions are provided primarily for debugging purposes.