Added unittests for RawData and String
Merge branch 'development' into bug80-py2and3-unittests
Added unittests for RawDataDecorator and StringDecorator

Fixes #80
Replaced lambdas and fixed some errors in py2and3 tests
Added false assert test to RawData contains test
Made py2and3 compatible with py2.5
Merge remote-tracking branch 'moritzs/bug80-py2and3-unittests' into development