Overhaul inf-elixir-send-* buffer lookupThis is a relatively complex flow that I've wanted to revisit for sometime. I will be uploading a diagram to the wiki that encapsulates mostof the flow.Also introduces a new `inf-elixir-set-repl` command which allows theuser to manually set what REPL they want the current buffer to sendto. This choice is remembered until the buffer is killed or thecommand is run again.

Write a slightly better error message

Bail out of `inf-elixir-project' if project root not found

Add "sent" commands to comint history

Update to v2.0.0

Update to v1.0.1

Add note to README about keybindings