avatars: add fallback avatar image

- Draws a generic person overlay in the case of a ringId being the
  only available name.

- Sets the conversation's username to the contact's ringId at
  initialization, if no registered name is available.

- Sets the presence at conversation initialization.

Change-Id: I1874b57719398acd6aa096b645f540ce3a528cf0
Reviewed-by: Kateryna Kostiuk <kateryna.kostiuk@savoirfairelinux.com>
13 files changed
tree: 464abc646115954ea407850ad5f905e34ddf8657
  1. Ring/
  2. .gitattributes
  3. .gitignore
  4. .gitreview
  5. compile-ios.sh
  6. COPYING