Document escaped semicolon for list
The very first note of the list documentation reads
A list in cmake is a
;
separated group of strings.
Strictly speaking "a\;b" consists of the 2 groups "a\" and "b" separated by a ;
but it is a list with only one item.
The above definition is not completely accurate:
more precision about escaped ;
is required, most certainly at the end of the note and probably in set
command documentation.