rewrote svm_save_model and added svm_serialize_model
changed interface for predict_probability
small addition to the spec
load_from_string method

is only a ugly hack for now, not sure if I ever want to rewrite the load
method into something that can parse a string
Merge branch 'add_predict_probability' into custom_stuff
Merge branch 'add_serialize_to_model' into custom_stuff