Changes on comments mockups

Main changes on the mockups:

• 3 dots vertical
• include dropdown with actions on mockup
• review font-sizes (level 1 & 2)
• Save/cancel on editing
• Nuxeo-dialog message with confirmation for delete
• scenario with zero comments
• load more comments on main thread
• reply (icon or text)

Things to consider:

• The 3 dots with extended actions, show only when the user has permissions to perform an action.
  Edit/Remove are the base actions that we provide, and by default, only the creator of the message can edit or remove it.

• Primary level of comments have: avatars with 24px + main texts with 13px + secondary texts 11px
• Secondary level of threads/replies have: avatars with 20px + main texts with 13px + secondary texts 11px

• If the user wants to delete a comment, there should be presented a nuxeo-dialog w/ confirmation dialog, with the following message:
  "Are you sure you want to delete this comment?"
  Buttons: Cancel/Delete

• Created a Zeplin project, with a link for styling inspect: https://zpl.io/VQEPXKn

New mockups attached.