Updating .NET documentation build process

Author: jimevans

rake-tasks/crazy_fun/mappings/visualstudio.rb

@@ -411,10 +411,6 @@ def handle(fun, dir, args)
 
  doc_sources = resolve_doc_sources(dir, args[:srcs])
 
- if ENV['DXROOT'].nil?
- fail "Sandcastle documentation tools not found. Documentation will not be created."
- end
-
  if ENV['SHFBROOT'].nil?
  fail "Sandcastle Help File Builder not found. Documentation will not be created."
  end