Add documentation of script attribute, param elements.
Merge pull request #61 from mknoszlig/master

Problem: model script attribute and nested param elements are not documented
Problem: documentation has been updated in generate file.
Solution: update original documentation in project.xml and README.txt
Also added a hint that the README.md is generated.
Problem: No contributers hint
Solution: Add contributers hint
Merge pull request #62 from sappo/master

Problem: documentation has been updated in generate file.
Problem: According to gsl docs, 'include' is deprecated.
Solution: Use the 'gsl from' directive instead.