Make audit of account group membership changes pluggable

Account group membership changes were logged in a database table.

Now, the audit log service allows to register listeners to group
member added and group member deleted events. A default listener logs
these events to the database as before. But additional listeners may
now be registered for these events using the GroupMemberAuditListener
interface.

Change-Id: I73872c26479a78be31bacc2cbc8eb850a097d473
Merge "Make audit of account group membership changes pluggable"
Add --json option to review SSH command

Add --json option to review SSH command for posting code review,
message and inline comments via SSH.  Command reads the review
input from text file in JSON format, that corresponds to REST's
ReviewInput entity:

  $ cat review.json | ssh host gerrit review --json <SHA1>

Bug: Issue 602
Change-Id: I7e6f84b878b835cb7ea144cddd99702116d69b57
Delete unused ProjectIndexer constructor and make class private

This class was originally used by googlesource.com's custom batch
indexer, but no longer is.

Change-Id: Ic9958d3cf643295797dc132fba84cfd2f53ae837
ChangeBatchIndexer: Join catch clauses where possible

Change-Id: I5c08ee785770497384d8daf1be8b4a2116cc76a0
Merge "Add --json option to review SSH command"