Added scheduling monad stack and simple execution function which uses forkIO.
Added module export for MonadSchedule (..).
Allowed hspec version to be above 1.3
Added cabal sandbox files to gitignore; updated dependencies in cron.cabal; added hspec tests for MonadSchedule and execSchedule functions.
Added description of scheduler to readme.
Fixed misuse of static thread delay. All delays will track on the next minute, and be as close as possible to zero seconds.
Merge pull request #9 from AndrewRademacher/master

Added scheduling monad stack and execution function which uses forkIO.