Add daemon instance to Jython shell session

Given that the Daemon instance contains all Guices injectors, all Guice
bindings can be reached from the Daemon instance.  Expose Daemon instance
to the Jython shell session as "d" variable.

For example to dump the global capabilities:

  >>> from com.google.gerrit.server.config import AllProjectsNameProvider
  >>> from com.google.gerrit.server.git.MetaDataUpdate import Server
  >>> from com.google.gerrit.server.git import ProjectConfig
  >>> i = d.sysInjector
  >>> allProjectsNameProvider = i.getInstance(AllProjectsNameProvider)
  >>> metaUpdateFactory = i.getInstance(Server)
  >>> md = metaUpdateFactory.create(allProjectsNameProvider.get())
  >>> cfg = ProjectConfig.read(md)
  >>> s = cfg.getAccessSection("GLOBAL_CAPABILITIES", True)
  >>> for p in s.getPermissions():
  >>> ...   print p
  ...
  accessDatabase [group Administrators]
  administrateServer [group Administrators]
  [...]
  streamEvents [group Non-Interactive Users]
  >>>

Change-Id: If5de7491e55002fff6078741deb43d1dc3ed855e

Documentation/dev-inspector.txt

@@ -180,11 +180,8 @@ defined in the interpreter:
 "schk" is "com.google.gerrit.server.schema.SchemaVersionCheck@5e8cb9bd"
 "ds" is "com.google.gerrit.server.schema.DataSourceProvider@6b3592c"
 "m" is "com.google.gerrit.lifecycle.LifecycleManager@6f03b248"
-"q" is "com.google.gerrit.reviewdb.server.ReviewDb_Schema_GwtOrm$$23@56d3384d"
 "Shell" is "com.google.gerrit.pgm.shell.JythonShell@61644f2d"
-"x" is "com.google.gerrit.reviewdb.client.PatchLineComment@518acfa7"
-"z" is "com.google.gwtorm.jdbc.Database@668dfd9b"
-"db" is "com.google.gerrit.reviewdb.server.ReviewDb_Schema_GwtOrm$$23@6a3ccb09"
+"d" is "com.google.gerrit.pgm.Daemon@28a3f689"
 
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gerrit-pgm/src/main/java/com/google/gerrit/pgm/Daemon.java

@@ -226,6 +226,7 @@ public class Daemon extends SiteProgram {
         shell.set("m", manager);
         shell.set("ds", dbInjector.getInstance(DataSourceProvider.class));
         shell.set("schk", dbInjector.getInstance(SchemaVersionCheck.class));
+        shell.set("d", this);
         shell.run();
       } else {
         RuntimeShutdown.waitFor();