Add package.json as per Issue #97

Added a package.json file to be used for PlatformIO integration.

Author: nigelb

package.json

@@ -0,0 +1,6 @@
+{
+    "name": "framework-arduinoapollo3",
+    "description": "Arduino Wiring-based Framework (Apollo3 Core)",
+    "version": "1.0.22",
+    "url": "https://github.com/sparkfun/Arduino_Apollo3"
+}