Hydrofracking background image [#53912853]

New image for background in Hydrofracking theme. This is far too big in terms of file size, however; we need to scale it down.

https://www.pivotaltracker.com/story/show/53912853
Replace Hydrofracking SVG background with PNG

[#53912853] This uses a smaller file-sized PNG for the background.

https://www.pivotaltracker.com/story/show/53912853
Merge branch 'master' into staging
Merge branch 'master' into staging

* master:
  Prevent "mass-assign protected attar" errors while migrating.
Merge branch 'refs/heads/master' into staging
Merge branch 'master' into staging

* master:
  Use transparent png for WaterModule_logo
  Add HAS NGS sequence logos. Modify CSS so there is more room for logos.
  Migration: sequence.rb add logo field. Add logo_helper & refactor layout
  sequence_run layout. TODO: Maybe with, we can reuse runtime layout.
  Extract activity-sequnce.scss from style.scss - include in runtimes.
  Stop using CDN for modernizer. (It was actually *really* slow! locally)
Merge branch 'master' into staging

* master:
  Add modernizer.min.js to precompile assets…
Merge branch 'master' into staging

* master:
  Fix CSS bug:  Footer in the middle of the page.  (⊙_◎)
Merge branch 'master' into staging

* master:
  More small CSS tweaks to enhance the visibility of sequence index pages.
  Add sequence info styles for Title and Description.
  Add sequence styles to ngs-climate and runtime (un-branded  default) css
Merge branch 'master' into staging

* master:
  activity_run.erb Don't clobber the style of #footer in runtime.css
Merge branch 'master' into staging

* master:
  Fix errors spec w guard: # https://github.com/dtao/safe_yaml/issues/10
  This test is working for me, un-pending it.
  New Transparent logo Assests for NatGeo HAS Sequences.
  this test now passes some of the time
  simplify feature spec, still not passing
  remove broken sourceMapping
  fix typo in file name
  fix double click running from the portal
  Preserve SequenceRun info using runnable_activity_path. &etc.
  Preserve SequenceRun info using runnable_activity_path. &etc.
  Add SequenceRuns to associate activity runs to a sequence.
  Add factory for activity with open response. Start Mock for OmniAuth.
  improve formatting of spec_helper comments
  Improve save_and_open_page hanlding
Merge branch 'master' into staging

* master:
  Guard for empty sequence logos
Merge branch 'master' into staging

[#54715018]
Merge branch 'master' into staging

* master:
  image_question_answers/_summary.html.haml: Guard against missing images
Merge branch 'master' into staging

* master:
  Home page listing of activities/sequences should be sorted by modtime.
  All activities/sequences indexes should sort by last modified date.
  Gemfile: Add time cop for time-sensitive testing.  (bundle install req)
  Add Travis and Code-Climate badges to the README.
  Tavis CI isn't calling rake db:migrate like I would hope it would...
  This was interacting badly with changes to spec_helper (visit ! defined)
  Fix spelling problem: [#56010414]
  Change 'See This Page' to 'Preview'.  [#55994072]
  Tweaking travis configuration (have to push to trigger a build sorry… )
  Add Travis CI configuration
  Unit test for SequenceRun
  Lightweight_activity.rb : Add run collection to activity model.
  Fixes for capybara poltergeist tests on Scott's machine
Merge branch 'master' into staging

* master:
  Fix anonymous activity listing on activity page.
Make sequences publishable. Extract publishable module.

User was modified, to add cancan methods for use outside controller.
Filtering logic in models/collection_filter.rb

Also separate collections for @community_activities and @official_activities
whitespace fix only.
Add 'Show Mine' list next to activities.

[#55992844]