Merge Revit2015 to master
Merge pull request #15 from theanh0512/Revit2015

Merge Revit2015 to master
Resolve merge issues and build configuration issues

- Defined user_local.props which references DynmoCore specific binaries
from Dynamo repo output directory.
- Based on this property sheet, the output for DynamoRevit projects are
directed to DynamoCore projects.
- It is expected that users will update it as per their needs.