Build analytics plugin against 3.0.0 plugin API

OutputFormat class was moved to its own top level package. gwtjsonrpc
dependency was removed from gerrit core and thus from the plugin API.
JavaSqlTimestampHelper was copied in json package in gerrit core.

Bug: Issue 10739
Change-Id: I1f720a924fdb1de39edc608a5d2413638535bb75
diff --git a/build.sbt b/build.sbt
index 74cfc91..59d1b6a 100644
--- a/build.sbt
+++ b/build.sbt
@@ -1,6 +1,6 @@
 enablePlugins(GitVersioning)
 
-val gerritApiVersion = "2.16.8"
+val gerritApiVersion = "3.0.0"
 
 val pluginName = "analytics"
 
@@ -12,7 +12,7 @@
   .settings(
     name := pluginName,
     resolvers += Resolver.mavenLocal,
-    version := "2.16-SNAPSHOT",
+    version := gerritApiVersion,
 
     scalaVersion := "2.11.8",
 
diff --git a/src/main/scala/com/googlesource/gerrit/plugins/analytics/common/DateConversions.scala b/src/main/scala/com/googlesource/gerrit/plugins/analytics/common/DateConversions.scala
index 3da8249..874dc0d 100644
--- a/src/main/scala/com/googlesource/gerrit/plugins/analytics/common/DateConversions.scala
+++ b/src/main/scala/com/googlesource/gerrit/plugins/analytics/common/DateConversions.scala
@@ -14,7 +14,7 @@
 
 package com.googlesource.gerrit.plugins.analytics.common
 
-import com.google.gwtjsonrpc.common.JavaSqlTimestampHelper
+import com.google.gerrit.json.JavaSqlTimestampHelper
 
 object DateConversions {
 
diff --git a/src/main/scala/com/googlesource/gerrit/plugins/analytics/common/GsonFormatter.scala b/src/main/scala/com/googlesource/gerrit/plugins/analytics/common/GsonFormatter.scala
index cca743d..d36cfef 100644
--- a/src/main/scala/com/googlesource/gerrit/plugins/analytics/common/GsonFormatter.scala
+++ b/src/main/scala/com/googlesource/gerrit/plugins/analytics/common/GsonFormatter.scala
@@ -16,7 +16,7 @@
 
 import java.io.PrintWriter
 
-import com.google.gerrit.server.OutputFormat
+import com.google.gerrit.json.OutputFormat
 import com.google.gson.{Gson, GsonBuilder, JsonSerializer}
 import com.google.inject.Singleton
 import java.lang.reflect.Type
@@ -45,4 +45,4 @@
     }
   }
 
-}
\ No newline at end of file
+}