Fbx importer test only if there is one key to determine if the import contain animation

We should test two key instead since one key is a constant value.

We have to make sure it did not break any current pipeline. But my guess is no. The question we should verify is, is users were putting only one key to create rigid skeletal mesh?

Having it wrong is not that critical since this is use to automatically choose the fbx import type (staticmesh, skeletalmesh and animation)

We should also be able to remove the 3ds MAX hack where we skip the translation and rotation curve because there is always one key in there.

Create an asset in Maya that have unskinned mesh with with only one key on the transform.

RESULT: You the fbx import will choose to import a skeletalmesh by default

EXPECTED RESULT: Since there is only one key, it should select staticmesh by default