Added a test class for StringBuilder

JsonGeneratorTests/StringBuilder.cpp

@@ -1,3 +1,8 @@
+/*
+ * Arduino JSON library
+ * Benoit Blanchon 2014 - MIT License
+ */
+
 #include "StringBuilder.h"
 
 
@@ -32,8 +37,8 @@ void StringBuilder::appendEscaped(const char* s)
             break;
 
 
-        default:
-            buffer[length++] = *s;
+        default:
+            buffer[length++] = *s;
             break;
         }