Add branch alias for 2.0 to composer.json
Add branch alias for 2.0 to composer.json

This is considered a best practice for composer. See here for details: http://getcomposer.org/doc/articles/aliases.md
isa-group/phploc,dennisdegreef/phploc,sebastianbergmann/phploc,ircmaxell/phploc,ravage84/phploc,shivanshuag/phploc