Merge pull request #1088 from karlnapf/develop

update multiclass ovr example
update news
added a proper equals method
added some first methods for equal methods on CSGObjects
first implementation of equals method (not completely working yet)
first set of unit tests for equals framework
mention equals framework in new features
added proper handling of string based types
new unit test for equal and string based types
first (compiling) sparse equals
fixe some typos and bugs
typos
add unit test for sparse vectors
add unit test for complex equals example