Add __str__ method
Fix name of generator
Support to_s
Fix license sentences
Merge pull request #433 from gintenlabo/fix-licenses

Fix license sentences (#429)
Merge pull request #431 from unnonouno/feature/python-str

Add __str__ methods to user defined objects
Merge pull request #432 from unnonouno/feature/ruby-str

Support to_s in ruby client
Fix command line description: refs #222
Add config examples of nearest_neighbor
Refactor cpp test of jenerator
Merge branch 'develop' into feature/client-const-reference
Write unit test for gen_argument_type