QtLocation map updates

[Dirk Hohndel]

I have done a somewhat coarse review of the code. A few minuscule complaints,
mostly about commit message formatting and random white space and coding
style things, but nothing of substance that I noticed reading the code.

I think I'll pull this today (just waiting for a note from Lubomir that he's ready for
me) and then we can all test this.

This may break things, but it looks really, really promising.

Of course, having this in Subsurface-mobile would be spectacular :-)

/D