Panda: dont treat <:> as a wordbreak. fixes #1

Thanks to moritz for finding the first bug!
Also lists modules instead of files when doing panda install<TAB><TAB>
Panda list <TAB><TAB> no longer lists avalible modules.
Perl6: using case statements. No longer escapes =.

I couldnt get --encoding\= to complete correctly. As a temporary
workaround, we have switched to the unescaped--encode= construct.
Updated README with some basic Info.