Now we can generate a fairly basic FS.

Added some test material

test/hello.txt

@@ -0,0 +1 @@
+Hello World!

test/test_image.json

@@ -0,0 +1,11 @@
+{
+  "files":
+  [
+    {
+      "name": "HELLO",
+      "ext": "TXT",
+      "file": "hello.txt"
+    }
+  ],
+  "output": "test.mffs"
+}