Merge release/4.6 to develop - NOT READY TO MERGE

There were a few merge conflicts we needed to resolve(some old that got wiped...).

* @jleandroperez  - could you fix the one in `NotificationDetailsViewController.m`
* @aerych - could you fix the one in `CommentContentView.m` and `ReaderCommentsViewController.m` (I believe you already did this here but it got wiped - https://github.com/wordpress-mobile/WordPress-iOS/commit/26e4018a11b9ce005b24c8d033ea6ab98f4647ae).