Patches for Yosemite

This gets rippled going on Yosemite.

After upgrading you have to re-install command-line tools prior to building:
$ xcode-select --install

Tested on both Mavericks and Yosemite.  Passes Travis.
@josh-ripple @niq
Consider:

    ten, major, minor = ver.split('.', 2)

(Reason: guarantees at most 3 parts for free.)

Actually, this is marginally better:

    parts = platform.mac_ver()[0].split('.')
    while len(parts) < 3:
        parts += ['0']
   self.__display = '%s %s' % (self.name, parts.join('.'))

(reason: works correctly for any number of parts;  shorter; doesn't do both count and split.)