Better "follow" button behavior

Closes #133 (closed)

• Button now becomes disabled when follow request is in progress and until confirmed.
• Shows "Request sent!" for locked accounts, allows for re-sending it again
• Tooltips for different states
  • tooltip for "Following!" telling that clicking it would unfollow,
  • tooltip for "Request sent!" telling that clicking will send follow request again
• Checks if response contains following: true and does delayed user fetching if it's not.
  • Up to 3 attempts to re-fetch user data until it becomes following: true with 500ms interval between each
  • If still unconfirmed after 3 attempts - does same thing as with locked accounts - shows "Request sent!"