#523 External SV Files re-creation

[StevenAZ]

If the user area is removed and replaced on disk "External SV Files" shows as "Not found".

Scenario is this:
- Create an area with verilog files
- Created an SV project file using a script (script does not include any "External SV Files" information in it)
- Launch Eclipse, import project
- Build Project, External SV Files created as expected
- Close project
- Exited eclipse
- Blew away the area, and re-created it.
- Re-Created SV Project file using script (same as above)
- Launch Eclipse
- Open Project (already imported)

The External Files shows as "Folder not found" or something simlar. Is this something that Eclipse can recover from? Should it for that matter, or is this a scenario where I should have removed the project and re-imported it?