Updates dependencies in project.clj to use latest versions and switches to using cheshire instead of clj-json.
Removes clj-json from dependencies.
Switches to using http.async.client instead of clj-http.
Removes .lein-failures from git.
Adds messages function for retrieving recent messages.
Adds join-room, leave-room, and stream-messages functions.
Merge branch 'feature/async-client'
Updates README.md with new functions.
Adds a warning about stream-messages to README.md.
Removes println in stream-messages and adds users and account function bindings; function names can probably be improved.
Changes use and require to :use and :require and fixes bugs in join-room and leave-room.
Cleans up stream-messages and changes its behavior to call a handler function, passing it a lazy seq of messages.
Changes indentation in stream-messages to be more readable.
Adds preliminary attempt at file upload to campfire
Fixes upload function.
comments out the mime-type field which appears to be unnecessary for file upload to campfire.
Fixes indentation in imports.
Merge pull request #1 from lore17/feature/upload-files

Feature/upload files
Merges changes from upstream repository and fixes conflicts.
Adds an empty line back to the readme that I had accidentally removed.