Bug fix for storing and accessing avatar uuids in user models

The plugin would no longer correctly import the UserModel module from Talk. This caused the plugin to no longer be able to store or access the avatar uuids in the talk users. This is now fixed.

Working release

Working release tested and working at: https://snorre.io

Fixed bug where only the fallback Gravatar avatar was returned.

Bug fix to fix avatar urls

Fixed bug causing undefined avatar id in the avatar URLs.

Initial release of gravatar plugin for live testing

Initial implementation of gravatar plugin

Adds avatar property to graphql User schema and a corresponding resolver to
create, if necessary, and return an avatar uuid.

Adds server route /avatar/:avatar to proxy avatar requests to Gravatar. It uses
redis cache to improve response times, and ETag http cache directive to enable
browser side caching.

Adds client side graphql container component and view component to render avatars.
Currently the Avatar slot is positioned so that the avatar ends up on top of the
comment rather than left of it. This could be fixed by external css stylesheet
floating the avatar slot and comment left (or something in that fashion).

Signed-off-by: Snorre Magnus Davøen <snorremd@gmail.com>