Added dynamic_form error_messages_for user created on signup page.

This fixes the bug where trying to create two users with the same email
simply results in the page being refreshed with no obvious error.
Merge pull request #177 from kyle-f/bugfix_add-user-errors-to-signup-page

User creation errors are not displayed on the user signup page
Fixes article deletion in admin. Solves #179
Merge branch 'master' of github.com:fdv/typo
Updates various dependencies including mini_magick to fix a security flaw.

2013-03-12 - Remote code execution
If a URL is from an untrusted source, commands can be injected into it for remote code execution with the ; character.

Affected versions:
All
Identifier:
CVE-2013-2616
Sources:
http://vapid.dhs.org/advisories/minimagick.html
http://direct.osvdb.org/show/osvdb/91231
Fixes access to the articles editor, broken by a previous commit.

Switching to a resourceful model broke various things, including articles deletion. Fixing article deletion route broke new article one. This commit breaks deletion again but at least fixes new articles.

TODO: actually fix article deletion! It's 4:22 AM so I'll do it when I sleep. Also write some tests as the get / post / delete actions seems not tested, leading to the above mentioned bugs.
Adds Travis support for Ruby 2.0 with MySQL, PgSQL and SQLite.

From http://westonplatter.com/blog/2013/testing-multiple-rubies-and-databases/
This should fix the travis integration
One more to figure out travis internals
Updates Gemfile to ensure adapter is loaded on Travis. Trying to avoid a Travis specific gemfile
Fixes travis build for postgresql
Moves vendor/plugins/localization to lib/localization.

Solves DEPRECATION WARNING: You have Rails 2.3-style plugins in vendor/plugins! Support for these plugins will be removed in Rails 4.0. Move them out and bundle them in your Gemfile, or fold them in to your app as lib/myplugin/* and config/initializers/myplugin.rb. See the release notes for more on this: http://weblog.rubyonrails.org/2012/1/4/rails-3-2-0-rc2-has-been-released.
Moves sidebar model as a lib.

This seems necessary to further move the plugins/sidebar* that need the sidebar model as libs so we can upgrade to Rails 4.0
Moving sidebars from vendor/plugins to lib to follow Rails 4.0 spcs.
Moves static sidebar from vendor/plugins to lib.
Moves category sidebar from vendor/plugins to lib
Moves xml sidebar from vendor/plugins to lib
Some refactoring so we don't need to create a lib/something_sidebar.rb for every sidebar plugin we create.
Moves the remaining sidebar plugins to lib:
Moves Typo textfilters from vendor/plugins to lib