First phase of Code block Auto-completion for merge into master

This submission includes pull requests: https://github.com/DynamoDS/Dynamo/pull/2608 and https://github.com/DynamoDS/Dynamo/pull/2503 that have been merged into the intermediate ```Intellisense``` branch that are now being merged into ```master```. 

This includes static completion of class members and instance members over declared variables:
![image](https://cloud.githubusercontent.com/assets/5710686/4518270/e87158b8-4c80-11e4-9af1-0e151907cb5d.png)


![image](https://cloud.githubusercontent.com/assets/5710686/4518323/528c34b8-4c84-11e4-9ecf-51b4484dc1dc.png)

Use ```if (!completions.Any())``` for better performance (we don't need to count the items, we just want to know if there is any).