Improve removal of 'update_terminal_cwd'

Replace all instances. (For some reason, 2 are appearing in PROMPT_COMMAND)

Don't match whitespace or semicolon.

Replace with no-op command ':'.

Author: scheib

bashrc

@@ -45,7 +45,7 @@ HISTSIZE=10000
 # Remove call to update_terminal_cwd if it doesn't exist.
 #   (it is defined by Mac OSX etc/bashrc, but not if terminal is screen)
 if [ "$(type -t update_terminal_cwd)" != function ]; then
-  export PROMPT_COMMAND="${PROMPT_COMMAND/ update_terminal_cwd;/}"
+  export PROMPT_COMMAND="${PROMPT_COMMAND//update_terminal_cwd/:}"
 fi
 
 # Supress "An instance of Visual SlickEdit is already being displayed..."