Analytics Revit version tracking

@ikeough @kronz @tatlin  PTAL

Example report: 
"Revit-R20130308_1515(x64)-0.7.2.2921"

This uses the precise build numbers. We will need to map them back to real versions, but will allow us to separate between main and SR releases if we wish to do so
Better to obtain version string from base class rather than obtaining it from UpdateManager. IMHO, UpdateManager should not be exposed outside DynamoCore.