Merge IntentInstaller's role into IntentCompiler

It resolves naming mismatch in naming of IntentProcessPhases and states
handled in the phases. It is described in ONOS-1064.

- Define FlowRuleIntent that enables flow rule level operation
  as an intent.
- Remove IntentInstaller interface
- Existing installable intents such as PathIntent, LinkCollectionIntent,
  OpticalPathIntent and MplsPathIntent now become non installable intents.
  Only FlowRuleIntent is categorized as installable intent now.
- Implement intent compilers for PathIntent, LinkCollectionIntent,
  OpticalPathIntent and MplsPathIntent. They generates FlowRuleIntents.
- Write unit tests for the newly created intent compilers according to
  the intent installers' unit tests
- Remove all intent installers and their unit tests

Change-Id: I22d6c7acb65a4c066145de0018bd0727f44bd54a
diff --git a/core/net/src/main/java/org/onosproject/net/intent/impl/phase/IntentProcessPhase.java b/core/net/src/main/java/org/onosproject/net/intent/impl/phase/IntentProcessPhase.java
index dfa9d11..ea5a590 100644
--- a/core/net/src/main/java/org/onosproject/net/intent/impl/phase/IntentProcessPhase.java
+++ b/core/net/src/main/java/org/onosproject/net/intent/impl/phase/IntentProcessPhase.java
@@ -21,7 +21,6 @@
 import java.util.Optional;
 
 import static org.onlab.util.Tools.isNullOrEmpty;
-import static org.onosproject.net.intent.IntentState.WITHDRAWN;
 
 /**
  * Represents a phase of processing an intent.
@@ -52,7 +51,7 @@
                 return new InstallRequest(processor, data, Optional.ofNullable(current));
             case WITHDRAW_REQ:
                 if (current == null || isNullOrEmpty(current.installables())) {
-                    return new Withdrawn(data, WITHDRAWN);
+                    return new Withdrawn(data);
                 } else {
                     return new WithdrawRequest(processor, data, current);
                 }
@@ -60,7 +59,7 @@
                 return new PurgeRequest(data, current);
             default:
                 // illegal state
-                return new CompilingFailed(data);
+                return new CompileFailed(data);
         }
     }