Reimporting a static mesh will reset Static Mesh Collision Presets

Collision presets are reset when reimported for any static mesh. If importing and overwriting the original mesh I would expect these to be wiped but when reimporting an updated version of the mesh I'm not sure these should be reset.

1. Open UE4
2. Import a Static mesh
3. Open in the Static Mesh Editor
4. Change the Collision Preset to anything other than Block All
5. Reimport the Mesh (right-click in CB or file menu options work)

Regression: No

Results: Collision Presets are reset to Block All on reimport

Expected: Should remember the collision preset settings.