Support for local Avatar images

[aliciam]

We also need this as not all our customers/reporters have avatars, but wish to see their logo on their user profiles.

https://bugnet.codeplex.com/discussions/392126

Doing this in a new LocalAvatar branch of my forked repo. Not planning on keeping images in DB (like for the project) but just as a simple stored file, with a prescribed name 32.jpg and 64.jpg where both files are created from a single uploaded file. Then these will be used if available, else Gravatar used if available. This way the BugNet_UserProfiles table does not need to be touched. Also, quicker to get files from here than transferring from the DB.

[aliciam]

Completed changes. Not the best way of doing it though, but gets my customers what they want: https://github.com/aliciam/bugnet/tree/LocalAvatar