Migrating unmigrated nodes

- XyzAdd
- XyzSubtract
- XyzNegate
- XyzScaleOffset
Optimizing migration functions

Avoid using Point.AsVector and Vector.AsPoint nodes
Migrating Revit node

- PointNormalDistance
Merge branch 'master' of https://github.com/DynamoDS/Dynamo
Add conditional checking using CBN into migration
Migrate nodes

- FacesByLine
- StructuralFraming
Tidying up the position of new nodes in one-to-many migrations
Tidying up node position
Merge branch 'master' of https://github.com/DynamoDS/Dynamo
Add node positioning
Merge branch 'master' of https://github.com/DynamoDS/Dynamo
Completing the migration of XYZ.cs

Migrated into CBN:
- XyzToPolar
- XyzToSpherical
- XyzFromListOfNumbers
- XyzComponents
- ReferencePtGrid
- XyzArrayAlongCurve
- EqualDistXyzAlongCurve

Changed the migration to assume all XYZs as Points:
- XyzLength
- XyzNormalize
- XyzBasisX, XyzBasisY, XyzBasisZ
- XyzScale
- XyzCrossProduct, XyzDotProductXyzStartEndVector

Not migrated yet:
- XyzAverage
Merge pull request #1469 from ellensi/master

Migrate nodes