v0.6.11 released

Just some cleanups and usability fixes:

• Raise a 400 error on malformed URLs with known handling instead of 500
• Don’t include subcategories with no indexable entries (e.g. all GONE/HIDDEN/etc.)
• Improve the admin dashboard
• Miscellaneous code cleanups

Also I forgot to announce v0.6.10, released back on September 1; the changes from v0.6.9 were:

• Let 401 Unauthorized status overcome a path alias
• Improve the tests
• Sort the “recent users” display on the admin dashboard