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/config/config.go

@@ -62,7 +62,8 @@ func Command(v *viper.Viper) (string, error) {
 	}
 }
 
-// environment is where FromEnvironment reads the settings: it notes each
+// environment is where WAFFromEnvironment and RProxyFromEnvironment read
+// the settings: it notes each
 // value for the log, and keeps the first error. It reads every setting
 // through v, the viper NewViper returns, and honours each setting's _FILE
 // form too.