Add logos to viewer

[ianagbip1oti]

Fixes #3

Adds a /logos/{engine} endpoint that searches for logos in a logos folder. If the filename is a prefix of the engine name, it will use that logo.

Sets the logo as a right aligned background image on the engine name.

The screenshots below show logos at their worst. It shows what happens if there is no logo. It shows what happens with long engine names that end up overlapping the logo.

[jhonnold]

Graham is working on Logos and i'll do some additional verification with that once it's ready. Will probably merge and launch sometime this weekend.

[ianagbip1oti]

Awesome. Just added a small tweak where the engine may have digits in their engine name. e.g., CT800