TODO

FUTURE:
*   set local variables in config, have them appear in shell
*   getting the menu to NOT have leading quotes
*   remove/edit history
    -> important for removing passwords if accidentally typed
*   improve library usage of executables
*   interprocess communication
    -> sharing of variables between chitin processes
*   remove trailing whitespace from lines somehow. maybe as a final transformation when you hit enter?
*   `other_ls = method(:ls)` would be cool. note that ls is mapped to a binary and is not actually a method
*   pass environment to child processes
*   tab complete ruby/shell things
*   post_processing for shell commands
    -> make it asynchronous and use pipes
*   ability to 'neuter' a command, so that it won't automatically be run
    -> i think i just did this in a commit (6/11/13)
*   grep through history
*   ability to pass objects to ruby programs without converting them to strings

QUIRKS:
*   menu doesn't erase itself sometimes
    -> cat and tabcomplete a file that is empty. output is correct but confusing
*   does not play nice with GDB if it is called within the bash profile file

FAILURES:
*   slashes in filenames
*   `include Math; sin(5)` fails
*   too many open pipes
    -> don't close them in the first place
*   unable to do "STDIN > ls > NULLOUT ^ NULLERR"
*   tab completion on # errors out and breaks chitin
*   `[4 + 5, ll]` fails

Questions:
*   Why do you have to do @line = '' in Coolline in order to not affect the
    history? History calls el.dup which creates a new object. It shouldn't
    matter if I do @line.clear on the original.

RELEASE
*   failures