[scribus] Save Not Setting Saved Status

[Craig Bradney]

Those of you who can check out 1.5.0svn (trunk), please do so and
re-test this. I have just committed what might be the first part of a
fix. I can certainly see 2 major differences:
- On saving, the file is not reset to modified (as the file watcher that
scans for changed pictures and disks no longer tracks the sla file itself)
- When multiple docs are opened and a file is noted to be modified, only
the docs that contain that picture that are open are marked as modified.
The others are left alone.

Please test, I will backport this to 1.4.0 in the coming days.

Craig