Jepsen 0.3.5

[Kyle Kingsbury]

Comrades and rivals,

Jepsen 0.3.5 is now available. This is a relatively small release. It
incorporates a new version of Elle which brings dramatic performance
improvements--several months of work here--and has a few quality-of-life
improvements.

## Bugfixes

- os.debian/install and remove now acquire locks, which means you can do
multiple debian-package-affecting operations concurrently against a
single node.
- Thread/sleep callsites now have explicit integer coercion, fixing a
crashes in newer JVMs/Clojure.

## API Changes

- control.util/grepkill! now matches the full pattern of the process,
rather than just the first 15 characters. This is particularly helpful
for killing, say, one out of several `java` processes.
- net/Net has been moved to net.proto/Net. All its functions are still
available in jepsen.net too.

## New Features

- checker.perf: nemesis specifications can now include `:hidden? true`,
which prevents them from appearing on graphs.

## Minor Changes

- fs-cache/deploy-remote! returns the remote path it uploaded, making it
easier to thread into other expressions.
- control.util/install-archive! now has docs that explain the use of
file:// URLs.
- net/drop! now uses existing SSH connections, making it faster
- net/drop! has a clearer docstring
- Elle 0.2.1
- SSHJ 0.38.0
- Ring 1.11.0

The latest version is now available on Clojars and GitHub, as usual. :-)

--Kyle