Add REST API for query/update/delete/enable/disable telemetry config

1. Add unit test for newly added REST APIs
2. Add codec and unit tests for TelemetryConfig
3. Split web package out from app package due to dep conflict

Change-Id: I85f52b2a7d059622e98832843bc9613cb8befa98
diff --git a/apps/openstacktelemetry/app/src/test/java/org/onosproject/openstacktelemetry/config/DefaultGrpcTelemetryConfigTest.java b/apps/openstacktelemetry/app/src/test/java/org/onosproject/openstacktelemetry/config/DefaultGrpcTelemetryConfigTest.java
index c56247f..89fc1d0 100644
--- a/apps/openstacktelemetry/app/src/test/java/org/onosproject/openstacktelemetry/config/DefaultGrpcTelemetryConfigTest.java
+++ b/apps/openstacktelemetry/app/src/test/java/org/onosproject/openstacktelemetry/config/DefaultGrpcTelemetryConfigTest.java
@@ -23,7 +23,7 @@
 import org.junit.Test;
 import org.onosproject.openstacktelemetry.api.config.GrpcTelemetryConfig;
 import org.onosproject.openstacktelemetry.api.config.TelemetryConfig;
-import org.onosproject.openstacktelemetry.impl.DefaultTelemetryConfig;
+import org.onosproject.openstacktelemetry.api.DefaultTelemetryConfig;
 
 import java.util.Map;