Typo on include/cyclone/body.h

intertia -> inertia
Removed uneeded line on src/body.hpp

Removed isAwake = true; from addForceAtBodyPoint, as it will already be set to true on addForceAtPoint
Corrected calculations src/pfgen.cpp

Corrected some errors pointed in issue #11, first noticed by @SomeAdrian
Corrected bug include/cyclone/core.h. Issue #10

Inversion was not inverting z nor x correctly. Fixes issue #10, spotted by @integeruser
Merge pull request #17 from LucasCampos/master

Fixed issues #10 and #11, and some minor changes