LPS-45403 Add URL title to KBArticle - Part 2

Hi Peter,

This branch is for merging into upstream 6.2.x.

This contains the following changes ...
- Reinstated getting the unique URL title using dash and number when needed
- Moved getUrlTitle to utility class
- Removed remote service method for getting article by URL title. I had introduced it in an earlier commit but we're not going to use if for doc importing purposes.
- I rebased on upstream 6.2.x. 

thanks,
Jim