Merge pull request #92 from jemc/master

Problem: Expression "class.description" used when possibly undefined
issue93: README.md file update / typos project.xml

The README.md file now stipulates that the license.xml file has
to be copied in order to generate a valid project.

The project.xml file contains typos for the main-entities.
Merge pull request #94 from fnchooft/issue93

issue93: README.md file update / typos project.xml