Refer.RandomFunctions to generate random Refer records.
(key ()) is a random string suitable for a key in a refer record.
These keys are strings of 1-10 random uppercase characters.
(value ?len ?lines ()) is a random string suitable for a value in a refer record.
?len is the maximum length of a line in the value (default: 60).
?lines is the maximum number of lines in the value (default: 10).
(keyset ?size ?key ()) is a random set of size (size ()) (default: < 10) refer record keys.
The keys are given by (key ()) (default: key).