regexp-search added, std lib loader changes, more REadme items

ml_string.h

@@ -4,9 +4,11 @@
 #include "ml.h"
 
 #include <string>
+#include <regex>
 
 
 // Replace a substring with a replacement string in a source string
 void replace_substring(std::string &src, const std::string &substr, const std::string &replacement);
 
-
+// Returns true if where contains regex
+bool regexp_search(const std::string &where, const std::string &regex_str);