closes#748
- Removed the alpha software warning
- Better error message output for the whole app - can now specify an error, a context, and a help message
- Improved invalid node version, start and stop messaging
- Listens for Ctrl+C and exits nicely
- Minor improvements to handling and errors with old DBs (temporary)
Extracts all express-server-related code in index.js to core/server.js, leaving index.js purely for booting up Ghost's core components in a sensible order.
Aside from the project's tidiness, this means that we can perform asynchronous configuration loading/checks before requiring any modules that read the config.