24 learn homepage and styles

[benlk]

Changes

• redoes learn.inn.org homepage (the cjet theme) in accordance with the wireframe in learn.inn.org wireframe #24: https://www.dropbox.com/s/wp8lyujmlss0641/learn-homepage-wireframes-v4.pdf?dl=0
  • removes old template partials
  • adds new search box, with background image
  • background image sizes are generated with shell script in img/resize-search.sh, so that we can easily cut a bunch of images at different sizes to accommodate different breakpoints and not load heavy images on smaller devices.
  • the array of boxes on the homepage is meant to be populated by text widgets.
  • email signup form copies a bunch of styles but its own layout from INN/inn.
• Updates the inn theme to branch 26-homepage-refresh of INN/inn.

For #24.

This PR was created to merge it into staging, and then we'll merge this to master and deploy to production when it's ready.

The PR from this branch into master contains conflicts; hopefully they're just CSS than can be regenerated.

[benlk]

Whereas:

• we seem to rather-frequently overwrite staging
• inndev.staging.wpengine.com likely hasn't had the redesign information stored in its database since summer 2017
• there are no copies of inndev.staging.wpengine.com's database in Dropbox's database backups folder from that time
• there are no .sql files in the shared Google Drive
• the only copies of inndev's SQL dumps that I have are as follows:

  -rw-r--r--  1 blk  staff   149M Mar  5 13:11 inndev-2018-03-05-33882dc.sql
  -rw-rw-r--@ 1 blk  staff   172M Mar  4 19:40 mysql.sql
  -rw-r--r--@ 1 blk  staff   153M May 30  2017 snapshot_inndev.sql
  

  • inndev-2018-03-05-33882dc.sql does not appear to have the learn homepage configuration, but it is correctly set up for learn.inndev.test to work
  • mysql.sql does not have domain mappings set up for learn.inndev.test
  • snapshot_inndev.sql likewise does not have domain mappings set up
• those are the only copies of the learn.inn.org-on-staging database that I can find
• the referenced INN/inn theme submodule branch is Homepage and interior styles refresh work inn#34

And:

• we rewrite staging from production often enough that we should be worried about losing data
• WPE only keeps like 30 days of backup snapshots in their backup folders

Therefore:

• we have lost all content work done on inndev.staging.wpengine.com for the eventual revamp of inn.org and learn.inn.org
• we need to do a better job of keeping track of that site's database when copying production to staging for whatever reason
• we ought to keep backups of the staging database ourselves (Dropbox/Google Drive) as long as staging is being used for specific work
• alternately, we should spin up a copy of inndev on another WPE instance for this work. Are we using inntest2.wpengine.com or innsandbox.wpengine.com for anything?

[benlk]

Closing this PR as abandoned. The content work has been restarted on a different DB, and theme work continues in other branches in this repo.