Moar stations

Moar space stations!
Moar ground stations!
MOAR SAVE VERSION NUMBER!!!

# aka: 
I made the space station generator into a loop so that it will spawn as many stations as random chance gives it.
These space stations are now in a slightly higher orbit to reduce the chance/frequency of stations in insanely tight orbits around small planets.

The number of ground stations generated should also be significantly higher as there are now 3 times as many chances to generate some. This might seem to produce some odd results such as tiny worlds with 7 starports, but when you look at the population figures and notice they have 180 million citizens ... well only 7 seems quite low especially since that means there's a city attached!

Bumped the save game version so it should be merged at the same time as #2969 and #1719

Andy