Made shipParts generate their own shape
SPACEShips now use shipPart shapes not sprites
Removed ship sprites
Fixed issue involving the thrusterPath algorithm
Made CGMutePath CGPath, then released properly

Causes bad access error
Changed all scene properties in node objects to myscene

fixed 3/5 issues
CGPathRef is an object type.
Hold a strong reference to it.
Merge pull request #24 from MecoKing/strong-references

Hold strong references to paths
Merge pull request #22 from MecoKing/ShipParts

Ship parts