Removing RSpec’s rake task, relaxing rake version

Removing rubyforge_project setting from gemspec.

2.1.0

Update development dependencies slightly.

Update contributors list.

Merge pull request #52 from JasonBarnabe/rails5.1-deprecation

Fix comment on delete_all deprecation version

Fix Rails 5.1 deprecation in cancel_jobs

Use :primary_key option if it exists.

No need to query the database more than once.

Cannot presume the instance exists.

Check if instance is still flagged for delta before deleting.

Update mysql2 development dependency.

Merge pull request #46 from sharetribe/previous-failed-job

Create a new job if existing job failed