Merge branch 'dev-spearce'

* dev-spearce: (33 commits)
  Use transactions to handle comments when possible
  Avoid opening extra ReviewDb connection in PatchSetInfoFactory
  Minor ORM cleanups to support other backends
  Add command to output a Protobuf message file for the DB
  Support gwtorm 1.2
  Fix reference of Database<T> to SchemaFactory<T>
  Support Velocity 1.5
  Move replication queue binding out of GerritGlobalModule
  Remove static initialization of Velocity
  Move WorkQueue out of GerritGlobalModule
  Support auth.type = CUSTOM_EXTENSION
  Extract Git /p/ module configuration
  Make WebSession an abstract interface
  Move GitRepositoryManager setup out of SchemaModule
  Move SmtpEmailSender to its own module
  Make Address, EmailHeader visible to other EmailSenders
  Disable SSH Keys in the web UI if SSHD is disabled
  Refactor how we tie the SSH objects into the HTTP injector
  daemon: Allow httpd without sshd
  Allow sshd.listenAddress = off to disable the daemon
  ...

Conflicts:
	gerrit-httpd/src/main/java/com/google/gerrit/httpd/GitWebConfig.java
	gerrit-server/src/main/java/com/google/gerrit/server/schema/SchemaModule.java

Change-Id: If957ce2eeb9b1de4ed2b134b0db129c336900442