Fix package structure

setup.py

@@ -8,6 +8,8 @@ setup(
     author='Trinh Anh Ngoc',
     author_email='atw1990@gmail.com',
     packages=find_packages(),
+    namespace_packages=['pydevd_plugins.extensions'],
     license='MIT',
     long_description=open('README.md').read(),
+    long_description_content_type='text/markdown'
 )