Add %Z to break up long lines?

[bbail]

Occasional script lines can grow rather long with conditionals and sublines.
How about a new tag %Z to indicate that the script line continues on the next line.
Z sort of illustrates the idea and isn' t presently used.

%s%t(5)a mess of conditionals%t(3)another mess of conditionals%t(6)etc

could be

%s%t(5)a mess of conditionals%Z
%t(3)another mess of conditionals%Z
%t(6)etc