Page editing instrumentation

This is a Bucket list of some areas (in the action=edit?) around which we need data to make some design decisions

Click tracking

 * Preview
 * Show Changes
 * Marking as a minor edit

Click tracking + content analysis

 * Edit Summaries (How many users provide edit summaries)

Possible design

 * upon [Save page] / [Show preview] / [Show changes] record the click action (using Extension:E3 Experiments' event tracking built on Extension:ClickTracking, as used on Community Portal)
 * include
 * whether "This is a minor edit?" is checked or not
 * the length of the edit Summary text, hence 0 means no summary provided
 * Can we check to see if the summary text was changed from the suggested defaults? Like, there's defaults when you undo or rollback.

Questions

 * Do we really want to track each click to check and uncheck "This is a minor edit?" Or just record it as part of the [Save page] / [Show preview] / [Show changes] event logging?