WYSIWYG Editor Link Popup support WINDOWS file links

We would like to support WINDOWS disk drives and shared drives links.
This should be done by allowing the user to select a file from it's hard drive using the Browse Button.

A warning should say

"You can select a file on a shared drive on your computer. Make sure that the file is accessible to other user from the same path (drive letter or windows shared drive)"

If the path is something like:

c:\folder\file.txt the URL should be file://c:/folder/file.txt

If the path is something like

\\MACHINE\folder\file.txt the URL should be file://///MACHINE/folder/file.txt (yes 5 slashes)