Gemfile: Update to latest "paper_trail_manager".

This will fix exceptions caused by bots hitting pagination pages with
invalid arguments.
Gemfile: Update "rails" to 3.0.17, which has security fixes.
Gemfile, etc: Add "guard", "spork", plugins and such.
Gemfile: Fix errors caused by not including spork on travis-ci.
Gemfile: Update to rails 3.1.8. Add rails_autolink.
Update DuplicateChecking to use new "foreign_key" syntax.
Improve Event::time_for to always return Time objects.
Remove obsolete "debug_rjs" configuration.
Workaround ri_cal relying on monkeypatch to Time removed in Rails 3.1.
Update event_spec to use Time.now, Time.zone.parse and raw date comparison because of Rails 3.1 changes.
Gemfile: Update to rails 3.2.8.
Gemfile: Use patched "validation_reflection" gem with Rails 3.2 support.
Update spec_helper_extensions to use Rails 3.x ::class_attribute.
Gemfile: Use my "loofah-activerecord" fork with Rails 3.2 patches.
Move "vendor/plugins" into "lib" per deprecation. Refactor loading.

* Make Rails 4.0 compatible changes by moving items from
  "vendor/plugins" into "lib" and adding them to "autoload_paths".
* Only add "lib" to LOAD_PATH, rather than entire "Rails.root".
* Eliminate "lib/ext.rb" and inline it into Application.
* Reorganize Application loading so paths are at the top.
Capistrano: Use a local copy deploy strategy.
Merge branch 'with_rails_3.2'

* with_rails_3.2:
  Capistrano: Use a local copy deploy strategy.
  Move "vendor/plugins" into "lib" per deprecation. Refactor loading.
  Gemfile: Use my "loofah-activerecord" fork with Rails 3.2 patches.
  Update spec_helper_extensions to use Rails 3.x ::class_attribute.
  Gemfile: Use patched "validation_reflection" gem with Rails 3.2 support.
  Gemfile: Update to rails 3.2.8.
  Update event_spec to use Time.now, Time.zone.parse and raw date comparison because of Rails 3.1 changes.
  Workaround ri_cal relying on monkeypatch to Time removed in Rails 3.1.
  Remove obsolete "debug_rjs" configuration.
  Improve Event::time_for to always return Time objects.
  Update DuplicateChecking to use new "foreign_key" syntax.
  Gemfile: Update to rails 3.1.8. Add rails_autolink.
Fix deprecations by updating partial calls to new format.
Fixed invalid deprecation by changing event_spec tag_list calls.
Fix stray use of "lib" in "config/initializers/database_yml_struct.rb".