Ghci-like handling of Ctrl-C, Ctrl-D in psci
Ghci-like handling of Ctrl-C, Ctrl-D in psci

- When Ctrl-C (UserInterrupt) is pressed, cancel the current input
- When Ctrl-D (End of Input) is pressed:
  - if the input is empty interpret as "there would be no more commands, you may
    :quit" and quit
  - if the input isn't empty interpret as "the end of the current command"
    and execute the current command (whenether it's single-line or multi-line mode)

michaelficarra/purescript,michaelficarra/purescript