Update jiff.app.src for hex.pm

Time for Jiffy to enter the world of Erlang package management.

src/jiffy.app.src

@@ -2,5 +2,8 @@
     {description, "JSON Decoder/Encoder."},
     {vsn, git},
     {registered, []},
-    {applications, [kernel, stdlib]}
+    {applications, [kernel, stdlib]},
+    {maintainers, ["Paul J. Davis"]},
+    {licenses, ["MIT", "BSD"]},
+    {links, [{"GitHub", "https://github.com/davisp/jiffy"}]}
 ]}.