allow string escaping (cheers multi)

conf/cf-lex.l

@@ -325,6 +325,11 @@ else: {
   quoted_buffer_init();
 }
 
+<QUOTED>\\\\	{ BUFFER_PUSH(quoted_buffer) = '\\'; }
+<QUOTED>\\["]	{ BUFFER_PUSH(quoted_buffer) = '"'; }
+<QUOTED>\\[\n]	{ BUFFER_PUSH(quoted_buffer) = '\n'; }
+<QUOTED>\\[^\\] cf_error("Unrecognised backslash escape");
+
 <QUOTED>\n	cf_error("Unterminated string");
 <QUOTED><<EOF>> cf_error("Unterminated string");
 <QUOTED>["]	{