Provide cleanup-orphan-multipart subcommand to riak-cs-admin

Provide a way for the cleanup orphan multipart function described in
the 1.5.0 release notes to be executed from the command line. This
removes the need for users who are upgrading from having to attach to
the Riak CS console and execute erlang functions.
Fix {error, disconnected} repainted with {error, notfound}
Reduce indentation
Remove unnecessary if clause
Kill copy (put_fsm and get_fsm) on client disconnect
haxk
Merge pull request #924 from basho/feature/cmd-line-multipart-orphan-cleanup

Allow multipart orphan cleanup to be run from command line

Reviewed-by: shino
Merge pull request #929 from basho/bugfix/handle-disconnected-notfound

Fix {error, disconnected} repainted with {error, notfound}

Reviewed-by: shino
Propagate an error tuple and add error logs

- Don't throw away an error tuple, propagate it and match
- Add error log via lager because output to terminal is often lost
Add test case to cleanup orphan MPs in 30 buckets

sum(pool sizes) < 30
Fix riak_client leak, stop it after use
Add limitations and side effect of previous fix
Merge pull request #933 from basho/bugfix/pbc-leak

Fix pbc leak in cleaning orphan MPs

Reviewed-by: kuenishi
Remove white space and add spec
Merge pull request #932 from basho/bugfix/kill-copy-on-disconnect

Bugfix/kill copy on disconnect

Reviewed-by: shino
Update release notes to the latest bugfix
Update to the comments
Merge pull request #934 from basho/bugfix/update-release-notes

Update release notes to the latest bugfix

Reviewed-by: kuenishi
Set riak_cs_multibag tag to 1.5.0
Fix wrongly used bucket list