Add overloaded open for String filenames

Author: facchinm

src/WiFiStorage.cpp

@@ -5,3 +5,7 @@ WiFiStorageFile WiFiStorageClass::open(const char *filename) {
 	file.size();
 	return file;
 }
+
+WiFiStorageFile WiFiStorageClass::open(String filename) {
+	return open(filename.c_str());
+}

src/WiFiStorage.h

@@ -8,6 +8,7 @@ class WiFiStorageClass
 	static bool begin();
 
 	static WiFiStorageFile open(const char *filename);
+	static WiFiStorageFile open(String filename);
 
 	static bool exists(const char *filename) {
 		size_t len;