Added svm install, restart, remove, clean, stop

Features new in 1.4
 svm install|create <instance_name>
  install a new Splunk instance from package file (see SPLUNK_SOFTWARE
& SPLUNK_VERSION
  in bashrc file) - uses new port numbers if required
 svm stop
  stop current Splunk instance
 svm restart
  restarts current Splunk instance
 svm remove
  removes current Splunk instance
 svm clean
  kills all running splunkd and python processes (perhaps a bit
aggressive for Python!)

Changed features in 1.4
 svm open
  starts Splunk instance if not already started
 svm list
  adds a 'Running' column to indicate running state of Splunk instances
 svm <instance_name>
  changes directory to $SPLUNK_HOME
 fixed autocompletion rules