Added an `Avatar` property to the `AvatarView`
Replaced the `imageView` in the `MessagesCollectionViewCell` with the `AvatarView`
Moved the `Avatar.playground` to the example project so users can play around and learn it capabilities.
Updated the example project and abstracted the `sampleData` to its own file.
Updated the organization for the project to `MessageKit` instead of `Hex bits`
Federico Zanetello
Rich Gabrielli
Nathan Tannar
MacmeDan
Steven Deutsch
Jesse Squires