Some changes for geometry in OpenMDAO

1. Added a new interface IStaticGeometry for geometry objects that are passed between components.
2. Changed interface for IParametricGeometry to be PEP-8 compliant.
3. Added a new variable for passing IStaticGeometry objects in the framework. This variable is a simple one that just checks the interface when passed.
4. The geometry component now has an output Geom variable to which an IStaticGeometry is assigned when an IParamtericGeometry i slotted on the component.