Unit tets for instruction JSON codecs

Fixed several bugs in codecs turned up by unit tests

Change-Id: Icddb31aa3d2cb58612a0578772d24ff5f113d073
diff --git a/web/api/src/test/java/org/onosproject/codec/impl/InstructionCodecTest.java b/web/api/src/test/java/org/onosproject/codec/impl/InstructionCodecTest.java
index 781f133..8bf4439 100644
--- a/web/api/src/test/java/org/onosproject/codec/impl/InstructionCodecTest.java
+++ b/web/api/src/test/java/org/onosproject/codec/impl/InstructionCodecTest.java
@@ -44,7 +44,7 @@
     JsonCodec<Instruction> instructionCodec;
 
     /**
-     * Sets up for each tests.  Creates a context and fetches the instruction
+     * Sets up for each test.  Creates a context and fetches the instruction
      * codec.
      */
     @Before