Updated version to 2.8.1

Updated project version and API to 2.8.1 to match latest Gerrit
release.

Change-Id: Ibcb22e6b998a8a7024f19622274c2e7ecbda1ab1

pom.xml

diff --git a/pom.xml b/pom.xml
index 7e3ca04..e938aea 100644
--- a/pom.xml
+++ b/pom.xml
@@ -22,10 +22,10 @@
   <groupId>com.google.gerrit.plugins</groupId>
   <artifactId>admin-console</artifactId>
   <packaging>jar</packaging>
-  <version>2.7</version>
+  <version>2.8.1</version>
   <properties>
     <Gerrit-ApiType>plugin</Gerrit-ApiType>
-    <Gerrit-ApiVersion>2.7</Gerrit-ApiVersion>
+    <Gerrit-ApiVersion>2.8.1</Gerrit-ApiVersion>
      <jettyVersion>8.1.7.v20120910</jettyVersion>
   </properties>