Multi-repl

[jonpither]

• [x] Limit output to REPL sessions only, at present all traffic through the nREPL connection is shared
• [x] send out the eval requests through the pipe
• [ ] embed alias in the eval code
• [x] Rename ops (i.e. repl-out -> multi-repl-forward-out, repl-eval -> multi-repl-forward-eval)
• [x] Unit tests around MR functionality
• [x] How to interupt
• [x] Remove deprecated watch functionality
• [x] Paredit
• [ ] Think about styling, font-locking
• [ ] #21 Clear nREPL requests