Tesselate NurbsCurve's with ASM before injection to Revit 2015

### Issue

http://adsk-oss.myjetbrains.com/youtrack/issue/MAGN-4680#

Zach was seeing enormous slowdowns when attempting to visualize `NurbsCurve`'s that were the result of `Surface`-`Surface` intersections.  ASM results in `NurbsCurve`'s with 500 control points for even simple plane-ellipsoid intersections.  Revit is very slow to tessellate these curves.  The core issue is that intersections should not result in such a large number of control points.  However, this is a very common workflow and it's not entirely straightforward to ask ASM to "just return less control points", so we need an immediate fix for this.  

### Fix

The simplest fix is provided here.  Instead of handing Revit Curve types, we pre-tessellate them with ASM.  Then we just hand GeomKeeper a bag of lines.  For `NurbsCurve`'s with a high number of control points, this vastly speeds up GeomKeeper.  For this workflow, we went from several minutes to tesselate (basically unusable), to a few seconds:

![tess](https://cloud.githubusercontent.com/assets/916345/4326257/661be8b2-3f6d-11e4-9655-ebb65f7874bb.PNG)

I know what you're thinking - "WOW!"  

I've also created a task for refining `Surface`-`Surface` intersection results:

http://adsk-oss.myjetbrains.com/youtrack/issue/MAGN-4690

### Reviewer 

@ikeough