Prevent the ObjectViewer (Shift+F10) from going kablooey with a NULL camera pointer.
Move SectorView lines initialization, fixes #2186
Merge remote-tracking branch 'fluffyfreak/FixObjectViewer'
Force gas giants to have some visible atmosphere

Workaround small scale heights for gas giants by increasing them
slightly. Increase gas giant temperatures in the 0 temperature
workaround.
init custom system atmosphere density to 0, and temp to 1K
Merge branch 'gas-giant-atmosphere'
Merge branch 'master' of https://github.com/pioneerspacesim/pioneer into JustLookingAgain