Issue 3200: "Depends on" field now uses strikethrough for submitted dependencies.

The "Depends on" field is used to indicate when one change depends on another.
It would be very useful if it could react when those dependencies are marked as
submitted by setting a strikethrough on the text. That way, users don't have to
click through to see whether or not the dependent change has been committed
yet.

Testing Done:
Manual testing: marked a dependency submitted, observed it show up with a
linethrough in the "Depends On" list for another review. All tests in djblets
and reviewboard pass.

Bugs closed: 3200

Reviewed at https://reviews.reviewboard.org/r/5348/
Mention that users might need mysql devel headers.

Trivial docs change.

Fixes bug 1746.
Clearcase often fails in multi-site mode because oids are not yet available on server

When people are submitting a review request, the oid of the old file version
and new file version are sent and used to retrieve the filename. However, the
new filename is usually not yet synced. Since the filename is not mandatory, we
can catch this exception and try to retrieve path from client filename and vob.

Testing Done:
Successfully created a review request before the replica was sent.

Bugs closed: 3183

Reviewed at https://reviews.reviewboard.org/r/5185/
Merge branch 'release-1.7.x'
Fix issues with trailing slashes and hg-history for HgWebClient.

The "hg-history" branch of the HgWeb implementation could strip off too much
stuff if people forgot to configure their server name with a trailing slash.
I've simplified the code and fixed the bug all in one go. Trivial change.

Testing done: Ran unit tests.

Fixes bug 3216.
Merge branch 'release-1.7.x'
Initialize logging before loading siteconfig.

My recent change to improve test times by reducing initialization ended
up swapping the log.init_logging() call and load_site_config(). This
resulted in a lot of annoying log messages for many commands, such as
`manage.py evolve`. This change restores the order.
Change the format for the indentation info keys.

The key used for recording indentation line pairs was a tuple.
Python is fine with this, but the JSON serializer was not. Instead, we
now serialize it to a string, which is safer.