Update CaConfig and ClientCaItem. Add INFO packet encoding and decoding.

Change-Id: I2118bfee05640ddbf20643fa07bf4c91eb7ebd06
diff --git a/tests/unit-tests/ca.conf.test2 b/tests/unit-tests/ca.conf.test2
index 17f058b..22cd83c 100644
--- a/tests/unit-tests/ca.conf.test2
+++ b/tests/unit-tests/ca.conf.test2
@@ -1,9 +1,8 @@
 {
-  "issuing-freshness": "720",
-  "validity-period": "360",
   "ca-info": "ndn testbed ca",
+  "max-validity-period": "86400",
   "supported-challenges":
   [
-      { "type": "PIN" }
+      { "challenge": "PIN" }
   ]
 }
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