Add the start of a custom gravity affector
Fix wrong BSA group name typo
Do some padding with zeros on the resource group name to avoid priority problems with more than 10 resource groups.
Scale adjustment factor should not be written back to cellref scale
Merge remote-tracking branch 'scrawl/master'
Merge remote-tracking branch 'scrawl/scale'
Implement Gravity particle affector effects
Merge remote-tracking branch 'zini/master' into nifogre
Don't create entities and particles when only the skeleton base is needed
Start a Nif-style particle emitter

Not complete yet (doesn't handle the vertical or horizontal direction/angle),
and should probably be renamed.
Handle the vertical and horizontal parameters of Nif particles

Note that 'horizontal' is mapped to rotate around the Z axis, not Y. The Nif
particle parameters seem to be set up to expect a normal OpenGL (Direct3D?)
orientation, rather than the 90-degree pitch offset of the game.
Keep particles in local space
Handle NiParticleColorModifier with Ogre's ColourInterpolator

Note that Ogre's ColourInterpolator has a maximum of six color stages. This
seems to be fine so far, but if we want anything better, we'll need a custom
affector for it.
Fix particle direction
added basic cell table
added flag columns to cell table
Look in exterior cells first (chargen_crate_01_empty is in the prison ship but also outside of it, the one outside needs to be disabled)
Fix wrong detection of diseases
added region column to cell table
Merge branch 'cell'