Support submitting Listed and Unlisted versions

[jvillalobos]

This is a tracker bug for the tasks needed to support submitting Listed and Unlisted versions as specified in this PRD. Here are the steps that we need for this (I'll file individual bugs):

1. Add channel field to version and set it on version submission. Add channel field to version and set it on version submission #3478
2. Set channel for all existing add-on versions. mozilla/addons-server#3467
3. Communicate changes to developers and update documentation. (Jorge)
4. Use channel to determine version visibility. Use channel to determine version visibility and updates #3529
5. Update editor tools to handle unlisted and listed versions. Update editor tools to handle unlisted and listed versions #3754
6. Enable channel selection on submission.
   1. New add-on submission flow. New add-on submission flow for Listed and Unlisted #3480
   2. New version update submission flow. New version update submission flow for Listed and Unlisted #3481
      1. New file update submission flow. New File update for Listed and Unlisted #3729
   3. Show channel in Status & Versions page. Show channel for versions in Status & Versions page #3482
   4. Update add-on visibility box and status sidebar. Update add-on visibility box and status sidebar for Listed and Unlisted versions #3483
7. Hide unneeded developer options when only unlisted versions have been submitted. mozilla/addons-server#3472
8. Cleanup:
   1. Don't reference is_listed in non test code stop referencing is_listed in production code #3745
   2. Remove old inline version/file upload remove and cleanup step-version-upload waffle #3790
   3. Remove is_listed from addon. Cleanup for Listed and Unlisted versions #3485

[diox]

(Edited description to turn this into a TODO list with links, so that we can easily find out what we have done and what is left, in order)

[eviljeff]

Everything done, bar a few bugs we'll fix, so closing.