Init cli submodule

intake/__main__.py

@@ -1 +1,3 @@
-print("hello world")
+from .cli import main
+
+main()

intake/cli.py

@@ -0,0 +1,11 @@
+import os
+import sys
+
+def main():
+    try:
+        print("Hello, world!")
+    except BrokenPipeError:
+        # See https://docs.python.org/3.10/library/signal.html#note-on-sigpipe
+        devnull = os.open(os.devnull, os.O_WRONLY)
+        os.dup2(devnull, sys.stdout.fileno())
+        sys.exit(1)