Add to RunCMake.Syntax test comments not separated by spaces

Extend the BracketComment5 test case to cover both bracket comments and
line comments starting immediately after a bracket comment closes.
Add to RunCMake.Syntax test \-escape cases

Add an Escape1 test case covering \-escape cases inside bracket, quoted,
and unquoted arguments.  Also cover comments immediately after quoted
and unquoted arguments on lines containing \# escapes.
Merge topic 'cmake-syntax-test-escaped-comment' into next

8640e52 Add to RunCMake.Syntax test \-escape cases
144068e Add to RunCMake.Syntax test comments not separated by spaces