Simply right click in your Solution explorer the file you wish to 'clone and replace':
It will bring up a dialog:
Enter the target (what you wish to replace), and replacement (what you will replace target with).
After executing, it will create new file replacing the target's file name next to the original. It will replace all case sensitive instances as well as Camel case instances of the string within the document.
Set variables
Save the target and replacement within the extension so you don't need to constantly enter those fields if doing heavy cloning.
Notes
This continues to be a work in progress; collaborators are welcome.