Missing Readline commands

[sdether]

Missing capabilities:

• C-l needs hook so shell can execute the clear command
• Word commands should use any non-alphanumeric as a word boundary
• Apple Command Key should work as Meta
• Kill buffer is a single field, should be a kill ring

Missing commands:

• M-Backspace kill word back
• M-D kill word under cursor
• M-y cycle through kill ring

[sdether]

Fixed in https://github.com/sdether/josh.js/tree/0.2.5