Update japanese release note for 1.4.2
Speed up manifest pruning

With many manifests (I'm testing 10k or so), this is _significantly_
faster than the from_list/to_list roundtrip.
Return updated manifests from Riak write

Previously we would write updated manifests to Riak, but would return
state ones from the function call. This could cause manifests that were
marked as `scheduled_delete` to get reverted back into the `active`, or
`pending_delete` state.
Fix bug in check for overwritten manifest versions that results in
deletion metadata being erroneously updated. This bug was masked by
the bug fixed by commit 87c6304ddbbeada7013f2cdb2e0974c2b18b2d4a.
Align ERL_MAX_PORTS with Riak default: 64000 (up from 4096, both lower than R16 default)
WebMachine / routing test
Add riak-erlang-http-client connection (non-poolboy) and configs
Implement total cluster disk usage stats (first draft)
Adjust cluster disk stats for JSON encoding, hook up to wm api endpoint
Extract user listing to non-WM module
Implement per user disk usage api call