Perlbrew verbose options for both available and list

A lot of time ago I submitted a patch to [perlbrew](http://perlbrew.pl) that aumented the output of the commands list and available in order to provide much more information to the user. For instance, the list command shows also when a Perl version has been isntalled. A few days ago I was thrown over an issue about how such output verbosity can break existing scripts. Therefore, I decided to implement the verbose option that, once enabled, will show the extra information, otherwise leaving them out and allowing for a much easier parsing of the command output by other applications. Now, it is quite clear that, as discussed in the issue this is a clear warning that it should be better to implement a way to keep a stable output while improving it. In other words, I do believe it is time to implement a kind of JSON (or alike) stable output leaving out the normal text be free to change by every release.