REPL can process shell commands
Better error reporting when loading extensions
Adding a command to run a shell command on the server
Better handling of 'foo.bar' syntax in repl
Cleaning up some old, unused code
Set a __server__ variable on all namespace extensions
Smarter command discovery for extensions
The Tasks namespace itself should not be callable
Add a utility method for converting a string to a bool
Adding more test cases for extension namespaces