rbenv-rehash: remove superfluous trap signals
rbenv-rehash: remove superfluous trap signals

A trap on the special signal EXIT is executed before the shell
terminates. EXIT actually covers SIGINT and SIGTERM as well, and
we don't need any extra traps for them.

See bash(1) and "help trap" in bash.

cehoffman/rbenv,cehoffman/rbenv,mediadoneright/rbenv,mediadoneright/rbenv,mediadoneright/rbenv,cehoffman/rbenv