Update changelog and contributor

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Fixed incompatible password reset token changes in Devise >= 3.1
Valid token for reset password tested.
Merge pull request #685 from brianvanburken/devise-fix

Fixed password reset token not working for Devise in current Errbit build.
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Signed-off-by: Arthur Neves <arthurnn@gmail.com>
Typo in English translation file.
Merge pull request #687 from brianvanburken/typo-corrected

Typo in English translation file.
added slack integration
added icons for slack integration
fixing bug, slack complaining of invalid json
ADD allow js client to add filters

A new `Airbrake.addFilter( callback )` method has been added.

Before sending any error, notifier.js will try each provided callback,
passing error data as parameter. If any returns false, error won't be
sent to errbit.

This allows users to define fine grain filters for their javascript
exceptions, like filtering out any error on scripts not coming from
their domain :

    Airbrake.addFilter( function( error ){
      return error.request_url.match( /^https?:\/\/my\.domain\.com\// )
    });
Merge pull request #689 from oelmekki/js_filters

ADD allow js client to add filters
Merge pull request #688 from jdguzman/slack_integration

Slack integration
Update README.md
Bump Rails version to 3.2.18 for security fixes.

For CVE-2014-0130
Merge pull request #691 from dylanahsmith/rails-security-fix

Bump Rails version to 3.2.18 for security fixes.
Remove debugger and ruby-debug from Gemfile

Those gems are specific to ruby version, and only used when debugging the app, so they dont need to be installed everytime
Add show action to the api v1 for problems

This allows a problem id to be passed to the problem api and only
information for that problem will be returned.
Add a problems err and notices in api show action