Add controls to select base and tip commits in the RB.DiffCommitListView

Review Request #1429 — Created Oct. 25, 2018 and updated Dec. 19, 2018, 8:58 a.m.

Information
Owner:	guest2060
Repository:	Review Board
Branch:
Bugs:
Depends On:
Commit:	d0a58dd...
Reviewers
Groups:
People:	fred

Description

The `RB.DiffCommitListView` can now optionally display controls for
selecting between base and tip commits to control what will be displayed
in the diffviewer. The actual logic for changing the diffs is not yet
implemented -- just the control itself.

Testing Done:
Ran JS tests.

Reviewed at https://reviews.reviewboard.org/r/10132/

Testing Done

Issues

Description	From	Last Updated
This is just a test	guest1299	Nov. 9, 2018, 11:17 p.m.
?????~	guest6459	Dec. 19, 2018, 8:57 a.m.
tewst~ ??	guest6459	Dec. 19, 2018, 8:58 a.m.

```
Test
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This is just a test
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reviewboard/diffviewer/models/diffcommit.py (Diff revision 1)
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?????~
```

Fix it!

reviewboard/diffviewer/models/diffcommit.py (Diff revision 1)
Show all issues
```
tewst~
??
```

You have a pending review.

Review Board 4.0.5 alpha 0 (dev)

Add controls to select base and tip commits in the RB.DiffCommitListView