Redo our URL scheme to use {% url %} tags

Review Request #359 — Created April 16, 2008 and submitted — Latest diff uploaded

Review Board SVN (deprecated)
458, 459
We've been using the old get_absolute_url() function in our templates, which works for the most part but has limitations. Using it on a User object doesn't work so well when installed in a subdirectory, requiring that we prepend SITE_ROOT and then slice the first "/". This gets ugly fast.

We've also been hard-coding other paths ("/account/login/", "/dashboard/", etc.), requiring prepending SITE_ROOT again.

Django's {% url %} tag provides a cleaner solution, allowing us to give certain pages names that we can refer to. Now something like {{SITE_ROOT}}{{submitter.get_absolute_url|slice:"1"}} turns into {% url user submitter %}.

This in theory could also give extensions in the future the ability to override certain pages if they wanted.

The result of this change is that we use get_absolute_url() a lot less for some things and never for users. We could move the rest of the get_absolute_url() calls in the future if we choose, though what we have works for now. We've also eliminated most references to SITE_ROOT in the templates.

There's some misc. fixes and cleanups in here too, such as using djblets's new user_displayname filter.
Made sure every page I tested worked properly in subdirectory installs. All the user links I could find now point to the correct location.