add "start" command

this allows users to start using the standard "npm start" command and acts as
documentation
Fix for issue #293
remove duplicated function
remove unneccessary anonymous function wrapper
use nested describes to have a global "beforeEach"

note that mocha will nicely indent the "test sections" as well when running
with the spec reporter :)
remove duplication
Merge pull request #298 from fdeberle/develop

Fix for issue #293
Merge pull request #299 from c089/add-start-command

add "start" command
Merge pull request #300 from c089/persistence-test-cleanup

Persistence test cleanup
Merge pull request #301 from mklose/master

remove duplication