0.4.2: Fixes, Rebalance, and Fixes

- Fixed Decouplers not completing contract tests when either exploding
or silently failing.
- Lowered decoupler default chance to explode from 12.5% to 6.25%.
- Lowered decoupler default chance to silently fail from 50% to 20%.
- Fixed fuel tanks with more than one resource initially leaking one
resource, and occasionally reloading with a different one leaking.
- Fixed more variables not loading properly.
- Changed "reliabilityDrain" variable names to "lifeTime" to coincide
with the fact that they hold the number of days a part will take to hit
0% reliability.
- Added Small Spare Parts Container to tech tree under "General
Construction" and fixed the base price to 100 FUNds.
- Set RocketParts resource unit cost to 1 FUNd per unit of RocketParts,
making a full Small Spare Parts Container cost 600 FUNds.