Hack in command-line specification of domain, cert and key

README.md

@@ -72,6 +72,18 @@ Probably other stuff. Email is big, and just keeps getting bigger.
 
 ## How
 
+### Building a binary
+
+```
+$ go build ur.gs/crockery/cmd/crockery
+$ sudo setcap 'cap_net_bind_service=+ep' ./crockery
+```
+
+The second step allows crockery to bind to the various low-numbered ports it
+needs (25, 587, 149, 993) **without** running as root. Don't bother with it if
+you're going to be running crockery as root, e.g., as a container or a single-
+purpose system.
+
 ### Initialize a new database
 
 ```