Add single quote to default_escaping

git-svn-id: https://klish.googlecode.com/svn/trunk@538 0eaa4687-2ee9-07dd-09d9-bcdd2d2dd5fb

lub/string/string_escape.c

@@ -6,7 +6,7 @@
 #include <stdlib.h>
 #include <string.h>
 
-const char *lub_string_esc_default = "`|$<>&()#;\\\"";
+const char *lub_string_esc_default = "`|$<>&()#;\\\"'";
 const char *lub_string_esc_regex = "^$.*+[](){}";
 const char *lub_string_esc_quoted = "\\\"";