Initial staging for economics view improvements.
Added label indicating current system and selected system, also if there are no items in a trade category.
Colour adjustments
Merge branch 'master' of github.com:Dessimat0r/pioneer into econ-improv
It could probably use some optimization and I'm not sure about exact correctness of math used, but it should be immeasurably better than what we had before.
Planetary Temperature Fix for Multiple Stars

Temperature for planets in multiple systems should now be calculated correctly, or approximately correctly in all cases.
Possibility of Life Respects Stellar Lifetimes

If system couldn't have existed long enough for life to form (based on one of its stars being too massive), there will be none, if it has, life will be scaled accordingly to the time it could have had to develop.
Also removed explicit checks for star types - those cases are either handled automagically by mass check (hot, massive stars), or are no longer checked for (life around white and brown dwarfs is considered unlikely and requiring rather special circumstances to form but *NOT* impossible).
Fix for temperature overflows during system generation.

Everything normalized to Earth's values like a good little Earth chauvinist should.
Fixed temperature calculation for binary orbiting planets in quarternary systems.

Bug due to misinterpretation of (rare) orbital configuration, fixed by reordering of conditions checked.
Merge branch 'temperature_overflow_fix' into multiple_system_temperature_fix
Added (obvious) check to functions checking if body is coorbiting.
code by Dessimat0r brought back from the dead (issue #210)
initial
Fix too short char buffer to fit string in trade comparison analysis.

For two systems with long names, (E.g. Epsilon E. and Kapteyn's Star) the
string would get clipped.
added tooltips and new buttons
cleanup
comment code and rename variable
NewUI graphics for the cpanel
fix Lua error when an axis binding is cleared in the settings screen
make KeyBindings::AxisBinding fields private