Move auto-complete code over to available -> enabled style

This continues the move toward the ability to turn things off with
everything turned on by default.

completion/available/ssh.completion.bash

@@ -0,0 +1,23 @@
+#!/bin/bash
+# Bash completion support for ssh.
+
+export COMP_WORDBREAKS=${COMP_WORDBREAKS/\:/}
+
+_sshcomplete() {
+    
+    # parse all defined hosts from .ssh/config
+    if [ -r $HOME/.ssh/config ]; then
+        COMPREPLY=($(compgen -W "$(grep ^Host $HOME/.ssh/config | awk '{print $2}' )" -- ${COMP_WORDS[COMP_CWORD]}))
+    fi
+
+    # parse all hosts found in .ssh/known_hosts
+    if [ -r $HOME/.ssh/known_hosts ]; then
+        if grep -v -q -e '^ ssh-rsa' $HOME/.ssh/known_hosts ; then
+        COMPREPLY=( $COMPREPLY $(compgen -W "$( awk '{print $1}' $HOME/.ssh/known_hosts | cut -d, -f 1 | sed -e 's/\[//g' | sed -e 's/\]//g' | cut -d: -f1 | grep -v ssh-rsa)" -- ${COMP_WORDS[COMP_CWORD]} )) 
+        fi
+    fi
+    
+    return 0
+}
+
+complete -o default -o nospace -F _sshcomplete ssh