index-v1 future proof test for uses-permission

The parser should accept additional elements to each
uses-permission entry, in case more XML attributes is added to
<uses-permission>.  <uses-permission> has had two attributes
since the beginning.

Other changes to this JSON data structure are bad index-v1
format, and will cause crashes:

* Removing an element e.g. null from a uses-permission entry
  would be invalid index-v1 JSON, since that structure mirrors
  the uses-permission AndroidManifest.xml element, which has a
  long standing fixed definition of name/maxSdkVersion.  That
  should crash so that fdroidserver authors know they are
  generating invalid index-v1.

* setting versionCode to anything but an int is invalid index-v1
  JSON, and should crash.  versionCode has been defined as an
  32-bit signed integer value since the beginning of Android.

* <uses-permission android:name=""> has been defined as a string
  since the beginning of Android.

https://developer.android.com/guide/topics/manifest/uses-permission-element.html

app/src/test/resources/guardianproject_index-v1.json

@@ -889,11 +889,15 @@
                     ],
                     [
                         "android.permission.WRITE_EXTERNAL_STORAGE",
-                        18
+                        18,
+                        null,
+                        "another fake future proofing test"
                     ],
                     [
                         "android.permission.VIBRATE",
-                        18
+                        18,
+                        1234567,
+                        "future proof test"
                     ]
                 ],
                 "versionCode": 100,