Added version file to common. It's also executable so it's accessible from shell.

monkey/common/version.py

@@ -0,0 +1,22 @@
+# To get the version from shell, run `python ./version.py` (see `python ./version.py -h` for details).
+import argparse
+
+MAJOR = "1"
+MINOR = "8"
+PATCH = "0"
+BUILD = "dev"
+
+
+def get_version(build=BUILD):
+    return f"{MAJOR}.{MINOR}.{PATCH}+{build}"
+
+
+def print_version():
+    parser = argparse.ArgumentParser()
+    parser.add_argument("-b", "--build", default=BUILD, help="Choose the build string for this version.", type=str)
+    args = parser.parse_args()
+    print(get_version(args.build))
+
+
+if __name__ == '__main__':
+    print_version()