Refs #12636. Form: a) Single Tick encode for {{10.line.content::s}}, b) new encoding type 'single tick'. Part a implemented. Test missing.

Fixed #7639. Update Manual.rst. Fake STORE_SIP so it can be used during processing sql1. Fixed bug that the currently form loaded record is available via STORE_RECORD.

Fixes #9074 - QFQ query with nested QFQ query failed if the outer QFQ query is a multi column query ( ='{{!' ). Fixed.

F7529 - Guarantee Sip Action plays only once. Update Doc, change from set to '' to removing SIP Key/Value completely.

Variable default: '0' is now treaten as a value. An empty string is still nothing >> no default given.

Rewrote some doc. Extend sql commands to be recognized in QFQ vars (have been already subscribed in that way in Manual.rst).

Fixes #6914. Final implemention of customized typeMessageViolation. Incl. unit tests. New escape mode 'C' - escapes ':' by '\'.' - useful for variables in variable definition.