* Change (re)indexing performance
For large Gerrit sites it could take a significant amount of time to reindex changes after an index schema
upgrade. Most of the time, however, reindexing computes diff in order to find
the list of changed files and size of the change. To address this issue we introduced
a new persistent cache: diff_summary. The purpose of this cache is to store everything
that is needed for change (re)indexing so that it doesn't need to be (re)computed again.
* ElasticSearch integration
Possibility to use ElasticSearch service instead of the embedded Lucene index.
There are still some TODOs like index schema upgrade and reindexing.
* New releases:
- JGit 4.5 released
- Gerrit 2.13 and 2.13.1 released
- Gerrit 2.12.5 released
* Code search UI in gitiles
The zoekt code-search  exposes a REST end point for performing queries
on indexed source code. Gitiles exposes UI for code-search  and utilizes the REST
end point from zoekt.
* Recommender for Reviewer Suggestion
Provide a recommender for suggesting change reviewer(s) .
Also provide an extension point so that plugin can provide own recommenders
for reviewer suggestion.
* Robot comments : provide native support in Gerrit for Robot comments.
Some refactorings done during the hackathon and a first change uploaded yesterday 
* Switched to Java 8:
how utilizing streams and lambda functions can reduce some boilerplate code.
* Merge Commit review: for merge commits add a new magic file /MERGE_LIST
which provides a list of all commits merged into the target branch via this merge.
It is possiblet o post comments on the /MERGE_LIST.
* Polygerrit UI switch
Add a possibility to switch between the GWT and PolyGerrit UI from the UI itself.
* JGit: implemented built-in clean and smudge filters to support LFS protocol.
The smudge filter is not yet fully finished as it currently cannot download missing large object(s).
* delete-project plugin: fix project (re)creation after its deletion, the fix is actually done in JGit
and is included in JGit 4.5 release.
* WIP: integrating JGit Ketch into Gerrit
- Bazel build for many plugins
- Basel build for GWT UI
- Work in progress Bazel build for PolyGerrit
- Upgrade GWT to 2.8-rc2
- Upgrade Buck to the latest version