Use find_packages to include sub-packages

setup.py

@@ -3,7 +3,7 @@
 
 from pathlib import Path
 
-from setuptools import setup
+from setuptools import find_packages, setup
 
 # Gets the long description from the README.md file
 readme_filepath = Path(__file__).parent / 'README.md'
@@ -12,7 +12,7 @@ with readme_filepath.open('rt', encoding='utf-8') as fd_in:
 
 setup(
     name='validata_core',
-    version='0.3.3',
+    version='0.3.4',
 
     description="Validata Core library",
     long_description=LONG_DESCRIPTION,
@@ -47,7 +47,7 @@ setup(
         'Programming Language :: Python :: 3',
     ],
 
-    packages=['validata_core'],
+    packages=find_packages(),
     include_package_data=True,
     package_data={
         'validata_core': ['validata_spec.json'],