Create a batch service plugin

The batch plugin provides a mechanism for building and previewing sets
of proposed updates to multiple project/branches/refs that should be
applied in a batch. These updates are built with Gerrit changes.

This initial change provides a mechanism to merge a change to a batch
with a single command.

Change-Id: I860fa82dfa6cfe2029c534c55593e580c6f8afc6
28 files changed
tree: 2c8723bb06258ca9ba32145c4b5ac8d80fa2fd93
  1. .gitignore
  2. BUILD
  3. LICENSE
  4. WORKSPACE
  5. bazlets.bzl
  6. pom.xml
  7. src/
  8. test/
  9. tools/