- heading + intro now say these are Data Controller's MPE_VALIDATIONS rules,
applied in the browser
- new paragraph on options MISSING: a regular missing prints as . unless the
option changes it (eg to blank); special missings are never affected
- CASE split out of the rule list: it is a character rule, and a special
missing always reaches the browser as an uppercase letter
- HARDREGEX and SOFTREGEX separated (SOFTREGEX warns rather than blocks, and
is ignored when the column also has a HARDREGEX)
- LinkedIn copy kept in sync
Behaviour confirmed against the deployed services on a real Viya estate.