Update and tweak

* Should be up-to-date for perlbrew v0.59
* Fix a bug involving long or short options. They now work both before and
  after commands. Examples:

    perlbrew --[TAB]
    perlbrew install --[TAB]

* Fix a big involving 'perlbrew install'. Available perls will now be shown
  whether or not there is an option after install. Example:

    perlbrew install --quiet [TAB]