Fix description in setup.py

setup.py

@@ -57,7 +57,7 @@ setup(
     version=version,
     packages=find_packages(),
     cmdclass={'build_py': LabelmeBuildPyCommand},
-    description='Simple Image Annotation Tool.',
+    description='Annotation Tool for Object Segmentation.',
     long_description=open('README.md').read(),
     author='Kentaro Wada',
     author_email='www.kentaro.wada@gmail.com',