Updating the LinkedArticleUrl

Updating the linked article url given the details provided by HP. Gets
the current site collection url and replaces it with the kms site
collection url.
Updated getting the XML file

Getting the XML filename was failing because Join-Path doesn't work with
absolute URLs.
Added a function for getting XML nodes for a specific environment
because this was required for CreateContentSources.
Updated the CreateContentSources.xml so that they don't start the crawl
automatically.