Rename the settings whose names do not say what they control (closes #234)

Applies the setting renames of the naming audit under the SWW_WAF_ and
SWW_RPROXY_ prefixes, with sneak's names for the IP reputation cache
time and the two time limits, which now take milliseconds. The rproxy
log field default_disposition becomes waf_backend_no_answer, and
config.Config and config.FromEnvironment become config.WAF and
config.WAFFromEnvironment. Go fields, test names and prose follow. No
aliases; nothing reads the old names.

Model: opus-5-5

internal/lookup/lookup.go

@@ -66,7 +66,7 @@ type Params struct {
 	URL string
 	// Timeout is how long a request waits for its client's first answer,
 	// and how long a request to GeoJS may take before it is abandoned
-	// (SWW_WAF_LOOKUP_TIMEOUT).
+	// (SWW_WAF_ASN_AND_COUNTRY_LOOKUP_TIMEOUT_MS).
 	Timeout time.Duration
 	// Wait is true when a setting needs each request's answer before the
 	// request goes on. Otherwise no request waits for one.