Allow resources to specify the name to use for links.

WebAPIResource subclasses can now set the link_name attribute to the
desired name for any links from other resources. Previously, this was
hard-coded to name_plural, and it still defaults to that.

This makes it easier to change a resource's name without affecting the
link, or to just choose a nicer name for links.

Reviewed at https://reviews.reviewboard.org/r/6125/
Merge branch 'release-0.7.x' into release-0.8.x
Release Djblets 0.8.7.
Bump to 0.8.8 dev.
Fix 'ctrl+s' in inlineEditors that use CodeMirror.

inlineEditor has two functions that save the contents: `save` and `submit`. Of
these two, `save` is really just meant to be an internal helper, and `submit`
is the one that does a lot of the necessary cleanup.

The handler for 'ctrl+s' was calling `save`, which caused the editor box to
disappear. Changing it to `submit` makes everything work correctly.

Testing done:
Opened an inline editor that used CodeMirror and hit ctrl+s. Saw the input box
disappear and be replaced with the rendered contents.

Fixes bug 3489.

Reviewed at https://reviews.reviewboard.org/r/6133/