dramatically different Marble/Subsurface-testing branch

[Dirk Hohndel]

So with all the frustration and bugs in Marble I decided to start from
scratch and went a dramatically different way. Instead of trying to take a
big hacksaw to Marble and strip out all the pieces we don't need I went
the other way. Took the latest Marble release (15.04.3 - which already
supports Qt5.5) and changed a hand full of things:
- the name
- the idiotic way Marble tries to open nonexisting files
- the need for libastro
- the popup with the Wiki link

So the new Subsurface-testing branch (you'll basically need to nuke your
directory and start over - this is a force push) is MUCH closer to
upstream which should allow us to report our bugs there and work with the
upstream developers to make Marble work better for us.

Daily builds are up. Please test to see how badly I broke things :-)

/D