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
deleted migration scripts
Merge pull request #301 from mklose/master

remove duplication
Merge remote-tracking branch 'upstream/master'
Merge pull request #302 from leider/master

deleted migration scripts
Merge pull request #303 from NicoleRauch/master

Fixed micro bug: caught escaped h and brought it back to where it belong...
Make  more explicit, added function names
Merge pull request #304 from fdeberle/develop

Make throw new Error('function not implemented') more explicit, added function names
Filter für vergangene Aktivitäten

- Test repariert (hat zuvor nur das Stubbing-Framework getestet)
Merge pull request #305 from marcphilipp/past-activities

Filter für vergangene Aktivitäten
README.md: * Switched to new 'npm start' command * Added example for running specific tests only
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