Bump version to 0.2.0-SNAPSHOT.
Update README with screenshot.
Add dependency instructions to README.
Add map extension test.
Simplify tagged value extension macro.

Instead of allowing a variable number of body forms, only accept one
expression as the body for `edn-value`.
Address kibit suggestions.
Added data-readers map to puget.data ns.
Add *color-scheme* dynamic var to control colors.
Set release version 0.2.0.
Merge branch 'release-0.2.0'