Rearrange image locations within the /static/ folder

[derek-keeler]

• Fix for #96
• Profile images are in their own dir, ignored by git
• static folder is now a bit simpler to manage via git
• move 'image' top-level folder to 'doc/' folder
• updated template/*html files affected by profile pic moves
• adjust config files to indicate where images are
• adjust README to compensate for images/ folder move

[derek-keeler]

❗ NOTE ❗

(from the issue attached)

This does cause a bit of a hassle for the admin of an existing service...