Edit tool does not select linked clips

[itsmattkc]

When splitting a clip (either with razor or edit tool), the newly spawned clips will continue to reference the old clips as linked.

The razor/edit tool in general need to be aware of linked clips which currently they aren't.

[itsmattkc]

When a clip gets "split", it runs a copy command to essentially make a perfect duplicate of itself. Obviously, duplicating the linked clips was not as good of an idea as it seemed at the time. This has been fixed, however it would be nice if Olive was self-aware enough to re-link clips if a bunch of them were clicked.

I'll leave this issue open, but I will put it on the backburner as it is no longer as app-breaking as it was before.

[itsmattkc]

If two clips are linked and one of them is removed, sometimes selecting the remaining clip will also make a blank selection where the other linked clip used to be.

[itsmattkc]

^ above fixed

[itsmattkc]

Basic support for splitting clips and relinking added. Support for the following still needs adding:

• Relinking after deleting a selection
• Relinking after splitting a selection
• Edit tool selecting linked clips
• Undo/redo unlinks all clips (now tracked in Undo/redo system is dysfunctional #72)

[itsmattkc]

It looks like implementing this will be fairly challenging, and I'm not even certain it'd actually be desirable. The edit tool isn't really for "per clip" manipulation, it's more for large spans of timeline area.

A way to implement this would be to make a separate "add to selection" function that checks for a selection on that track with those in/out points, and if they're covered, add them to an existing (otherwise just make a new selection object). This would also fix a potential future problem once you can make multiple edit tool selections by holding shift (not yet implemented) to prevent you from selecting the same area twice. It would be less efficient than the current code, but the functionality may outweigh it.

[itsmattkc]

Finally implemented this (using a better algorithm than the aforementioned as alluded to in #86). I was considering not implementing this at all for a while because it felt like it might be awkward. But since I didn't know, and the select code had been cleaned up to allow for this to be added relatively easily, I gave it a shot. Honestly, personally, I do find it awkward, but I can also see how it might be more intuitive for some people (which is also why I didn't dismiss it despite thinking there was a chance it wouldn't work). Therefore, it is now fully implemented and exists, but it's been disabled by default. This functionality can be added by checking "Edit Tool Selects Links" from the "Tools" menu.