Implement instance summary api for native scheduler

dataqa@lda01:~$ falcon instance -type process -name processMerlinNative -summary 
ERROR: Bad Request;<?xml version="1.0" encoding="UTF-8" standalone="yes"?><instancesSummaryResult><status>FAILED</status><message>ua1/org.apache.falcon.FalconException::javax.ws.rs.WebApplicationException: javax.xml.bind.UnmarshalException: unexpected element (uri:&quot;&quot;, local:&quot;instancesSummaryResult&quot;). Expected elements are &lt;{}result&gt;
ua2/org.apache.falcon.FalconException::javax.ws.rs.WebApplicationException: javax.xml.bind.UnmarshalException: unexpected element (uri:&quot;&quot;, local:&quot;instancesSummaryResult&quot;). Expected elements are &lt;{}result&gt;
</message><requestId>ua1/878228784@qtp-477289012-155 - 0083a904-3dd6-4f37-8335-14c266c71e93
ua2/878228784@qtp-477289012-155 - 0083a904-3dd6-4f37-8335-14c266c71e93
</requestId></instancesSummaryResult>

2016-01-11 12:11:04,329 ERROR - [785536989@qtp-536122141-26 - 6d22f7db-7037-415d-8ba1-493ab7ccb8b9:dataqa:GET//instance/summary/process/processMerlinNative] ~ Failed to get instance summary (AbstractInstanceManager:263)
org.apache.falcon.FalconException: Not yet Implemented
	at org.apache.falcon.workflow.engine.FalconWorkflowEngine.getSummary(FalconWorkflowEngine.java:382)
	at org.apache.falcon.resource.AbstractInstanceManager.getSummary(AbstractInstanceManager.java:258)
	at org.apache.falcon.resource.InstanceManager.getSummary(InstanceManager.java:126)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:497)
	at com.sun.jersey.spi.container.JavaMethodInvokerFactory$1.invoke(JavaMethodInvokerFactory.java:60)
	at com.sun.jersey.server.impl.model.method.dispatch.AbstractResourceMethodDispatchProvider$TypeOutInvoker._dispatch(AbstractResourceMethodDispatchProvider.java:185)
	at com.sun.jersey.server.impl.model.method.dispatch.ResourceJavaMethodDispatcher.dispatch(ResourceJavaMethodDispatcher.java:75)
	at com.sun.jersey.server.impl.uri.rules.HttpMethodRule.accept(HttpMethodRule.java:288)
	at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:147)
	at com.sun.jersey.server.impl.uri.rules.ResourceClassRule.accept(ResourceClassRule.java:108)
	at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:147)
	at com.sun.jersey.server.impl.uri.rules.RootResourceClassesRule.accept(RootResourceClassesRule.java:84)
	at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1469)
	at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1400)
	at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1349)
	at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1339)
	at com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:416)
	at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:537)
	at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:699)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)
	at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)
	at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1221)
	at org.apache.falcon.security.FalconAuthorizationFilter.doFilter(FalconAuthorizationFilter.java:108)
	at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)
	at org.apache.falcon.security.FalconAuthenticationFilter$2.doFilter(FalconAuthenticationFilter.java:188)
	at org.apache.hadoop.security.authentication.server.AuthenticationFilter.doFilter(AuthenticationFilter.java:572)
	at org.apache.hadoop.security.authentication.server.AuthenticationFilter.doFilter(AuthenticationFilter.java:542)
	at org.apache.falcon.security.FalconAuthenticationFilter.doFilter(FalconAuthenticationFilter.java:197)
	at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)