Merge pull request fhessel#16 from fhessel/fix-empty-header-names

Return empty string instead of invalid null pointer, Closes fhessel#14

Author: fhessel

https/HTTPRequest.cpp

@@ -39,7 +39,7 @@ std::string HTTPRequest::getHeader(std::string name) {
 	if (h != NULL) {
 		return h->_value;
 	} else {
-		return NULL;
+		return std::string();
 	}
 }