Add CLI to run any Python program based on argparse

Implements issue #519.

gooey/__main__.py

@@ -1,12 +1,13 @@
-# '''
-# Delegates arguments to the main Gooey runner
-#
-# For use when run directly from command line with the -m (module) flag:
-#
-#   e.g. $ python -m gooey
-#
-# '''
-#
-# from gooey import application
-#
-# application.main()
+'''
+Delegates arguments to the main Gooey runner.
+
+For use when run directly from command line with the -m (module) flag:
+
+  e.g. $ python -m gooey
+
+'''
+
+from gooey.cli import main
+
+if __name__ == '__main__':
+    main()

gooey/cli.py

@@ -0,0 +1,18 @@
+'''The command line interface.'''
+
+import sys
+from importlib import import_module
+
+from gooey import Gooey
+
+
+def main(args=None):
+    args = args or sys.argv[1:]
+    module_path, function_name = args[0].split(':')
+    if len(args) > 1:
+        if args[1] == '--':
+            del args[1]
+    sys.argv = ['gooey', *args[1:]]
+    module = import_module(module_path)
+    function = getattr(module, function_name)
+    return Gooey(function)()

setup.py

@@ -33,6 +33,7 @@
     install_requires=deps,
     include_package_data=True,
     dependency_links = ["http://www.wxpython.org/download.php"],
+    entry_points={'console_scripts': ['gooey = gooey.cli:main']},
     classifiers = [
         'Development Status :: 4 - Beta',
         'Intended Audience :: Developers',