Merge pull request #23 from ptommassen/feature/document-operation-refactoring

- allow data handlers to create their own document operations
Updated to new IOS
Merge branch 'release/I_0.0.2.11_PRERELEASE'
[maven-release-plugin] prepare release mobbl-core-framework-0.0.2.11
[maven-release-plugin] prepare for next development iteration
Update README.md
- check preconditions of dialogs