Updated version for next release cycle
Update docstring of defsystem to new protocols. Fixes #4.
Merge pull request #5 from ordnungswidrig/fix-defsystem-docstring

Update docstring of defsystem to new protocols. Fixes #4.
Use symbols for components in defsystem

Makes defsystem consustent with defrecord and deftype.

Closes #3
Updated project.clj, release notes and readme for 0.2.1
Merge release/0.2.1