Add gerrit-acceptance-tests

This change introduces an infrastructure for testing Gerrit daemon via
REST and/or SSH protocols. Gerrit daemon is run in the headless mode and
in the same JVM where the tests run. Besides using REST/SSH, tests can
also access Gerrit server internals to prepare test environment and to
perform assertions.

A new review site is created for each test and Gerrit daemon
is started on that site. When test finished the Gerrit daemon is
shutdown.

A purpose of this change is to initiate writing of acceptance tests
in order to minimize the probability of introducing regressions in
Gerrit.

The acceptance tests may be expensive to run each time when Gerrit is
built. Therefore, they run only during the verify phase.

Change-Id: I8c8a0f00f82d3dffc777d5f9ba6d79b8b82a7d81
Signed-off-by: Sasa Zivkov <sasa.zivkov@sap.com>

pom.xml

@@ -91,6 +91,8 @@ limitations under the License.
     <module>gerrit-extension-api</module>
 
     <module>gerrit-gwtui</module>
+
+    <module>gerrit-acceptance-tests</module>
   </modules>
 
   <profiles>
@@ -571,6 +573,12 @@ limitations under the License.
         <version>0.5.1-r1095809</version>
       </dependency>
 
+      <dependency>
+        <groupId>org.apache.httpcomponents</groupId>
+        <artifactId>httpclient</artifactId>
+        <version>4.0</version>
+      </dependency>
+
       <dependency>
         <groupId>com.jcraft</groupId>
         <artifactId>jsch</artifactId>