Fix MacPorts port name for pkg-config.
Merge pull request #1717 from mbaltaks/master

Fix MacPorts port name for pkg-config
Don't enforce full meta-packages.
Don't query that way, it leaks false packages.
Because libxslt-dev is pure virtual.
Because ncurses-dev is virtual.
homebew -> homebrew typo fix
allow different java versions on ubuntu, fix #1719