Refactoring of IntentId based APIs

- getIntent
- getIntentState
- getInstallableIntents

Change-Id: I6d2073dfa165e0e5adcef46fe5908b563b481a43
diff --git a/core/api/src/test/java/org/onosproject/net/intent/IntentServiceTest.java b/core/api/src/test/java/org/onosproject/net/intent/IntentServiceTest.java
index 9dce4f1..7ae00aa 100644
--- a/core/api/src/test/java/org/onosproject/net/intent/IntentServiceTest.java
+++ b/core/api/src/test/java/org/onosproject/net/intent/IntentServiceTest.java
@@ -91,7 +91,7 @@
             @Override
             public void run() {
                 assertEquals("incorrect intent state", IntentState.INSTALLED,
-                             service.getIntentState(intent.id()));
+                             service.getIntentState(intent.key()));
             }
         });
 
@@ -112,7 +112,7 @@
             @Override
             public void run() {
                 assertEquals("incorrect intent state", IntentState.WITHDRAWN,
-                             service.getIntentState(intent.id()));
+                             service.getIntentState(intent.key()));
             }
         });
 
@@ -140,7 +140,7 @@
             @Override
             public void run() {
                 assertEquals("incorrect intent state", IntentState.FAILED,
-                             service.getIntentState(intent.id()));
+                             service.getIntentState(intent.key()));
             }
         });
 
@@ -163,7 +163,7 @@
             @Override
             public void run() {
                 assertEquals("incorrect intent state", IntentState.FAILED,
-                             service.getIntentState(intent.id()));
+                             service.getIntentState(intent.key()));
             }
         });
 
@@ -255,7 +255,7 @@
             @Override
             public void run() {
                 assertEquals("incorrect intent state", IntentState.INSTALLED,
-                             service.getIntentState(intent.id()));
+                             service.getIntentState(intent.key()));
             }
         });