Fix: Change wording on e2e to make a little more clear

* Add IPreMessageUpdatedPrevent, Extend & Modify

* Add IPostMessageUpdated

Actions markup is output twice, in immediate succession: 
https://github.com/RocketChat/Rocket.Chat/blob/135c6f8e1bb204cd7b07682dec8e189144fe3871/packages/rocketchat-message-attachments/client/messageAttachment.html#L152-L158

@ubarsaiyan and @ggazzo - Please review and get this merged asap. Did no one even look at this feature before it went in release?

Closes #2922
Closes #4706

This PR adds a personal preference for what timestamp format to use:
![2018-06-16_21-26-48](https://user-images.githubusercontent.com/39674991/41501824-ffb5f034-71ab-11e8-813e-8a2c724fc84b.png)

**Default** uses the timestamp formats (usually `LT` and `LLL`) defined in admin settings.
**12-hour** uses a 12-hour format (`6:30 PM` or `January 3, 2018 6:30 PM`)
**24-hour** uses a 24-hour format (`18:30` or `January 3, 2018 18:30`)

* Fix #11901: Adding scroll bar to read receipts modal

* Using a pure CSS solution

* Fixing properties order

* Removing aditional space

Related with #11663, but I added a bug removing `t` function on this PR 😬 https://github.com/RocketChat/Rocket.Chat/pull/11728

Now we're translating 🗣️ 🌎 🌍 🌏 

![screen shot 2018-09-04 at 10 20 55 am](https://user-images.githubusercontent.com/2047941/45033836-30e28000-b02c-11e8-8726-96d8780eb92b.png)

Closes #11696 

Spacement: 

![screen shot 2018-09-11 at 9 51 23 am](https://user-images.githubusercontent.com/2047941/45361388-6ea15480-b5a8-11e8-8cb5-f01c6cd4cc49.png)

wrong "users" label: 
![screen shot 2018-09-11 at 9 56 57 am](https://user-images.githubusercontent.com/2047941/45361634-233b7600-b5a9-11e8-8948-3e2d1c6eeb36.png)

Closes #11651 

This was broken by adding a wrong css class in [this commit](https://github.com/RocketChat/Rocket.Chat/commit/831f757f12a7d646a8f3819cd2f3f5af3cecd1c1#diff-ff868971f6509568c40009e48cbae836), causing the wrong click handler to be executed.

Also removed a warning about the deprecated api `createObjectURL`.

Closes #11998