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/coreruleset/ghost.conf

@@ -3,7 +3,7 @@
 # rules it switches off, so this file is loaded before the Core Rule Set's
 # rules. Each comment names a request a rule refused. An exclusion on a field of
 # a body applies only when the query has no parameter of that name, so it
-# matters only while SWW_WAF_CORE_RULE_SET_BODY_LIMIT is set.
+# matters only while SWW_WAF_CORE_RULE_SET_BODY_INSPECTION_SIZE is set.
 #
 # Ghost's admin and its integrations call the Admin API under /ghost/api/admin/,
 # themes and Ghost's own scripts call the Content API under /ghost/api/content/,