Split the core receive logic out of the SSH code

We need to reuse the basic commit receive logic in both the SSH and
the HTTP code in order to support upload over http:// via the new
smart HTTP Git protocol.

Move the bulk of our Receive logic into the new shared ReceiveCommits
class, constructing it on a per-request basis out of the inherited
Git repository and project control instance.

Change-Id: I43ffd343aac5008c0f9446847e37fcb67d818478
Signed-off-by: Shawn O. Pearce <sop@google.com>

gerrit-server/src/main/java/com/google/gerrit/server/config/GerritRequestModule.java

@@ -21,6 +21,7 @@ import com.google.gerrit.server.IdentifiedUser;
 import com.google.gerrit.server.RequestCleanup;
 import com.google.gerrit.server.account.AccountResolver;
 import com.google.gerrit.server.account.GroupControl;
+import com.google.gerrit.server.git.ReceiveCommits;
 import com.google.gerrit.server.mail.AddReviewerSender;
 import com.google.gerrit.server.mail.CreateChangeSender;
 import com.google.gerrit.server.mail.ReplacePatchSetSender;
@@ -43,6 +44,8 @@ public class GerritRequestModule extends FactoryModule {
     bind(GroupControl.Factory.class).in(SINGLETON);
     bind(ProjectControl.Factory.class).in(SINGLETON);
 
+    factory(ReceiveCommits.Factory.class);
+
     // Not really per-request, but dammit, I don't know where else to
     // easily park this stuff.
     //