add readme and spdx header

README.md

@@ -0,0 +1,7 @@
+# trout bot
+
+Inspired by [Wikipedia](https://en.wikipedia.org/wiki/Wikipedia:Whacking_with_a_wet_trout], this bot lets you whack others with a wet trout.
+
+## License
+
+AGPL 3.0 only, see LICENSE.md

trout.py

@@ -1,4 +1,5 @@
 #!/usr/bin/env python
+# SPDX-License-Identifier: AGPL-3.0-only
 
 import pleroma
 import qtoml as toml