Update primus to the latest version 🚀

[greenkeeper]

Version 7.0.0 of primus just got published.

Dependency	primus
Current Version	6.1.0
Type	devDependency

The version 7.0.0 is not covered by your current version range.

Without accepting this pull request your project will work just like it did before. There might be a bunch of new features, fixes and perf improvements that the maintainers worked on for you though.

I recommend you look into these changes and try to get onto the latest version of primus.
Given that you have a decent test suite, a passing build is a strong indicator that you can take advantage of these changes by merging the proposed change into your project. Otherwise this branch is a great starting point for you to work on the update.

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Release Notes

Server sent pings

In this release we have reversed the direction of ping/pong messages. Pings are now sent from server to client to work around issues generated by throttled timers on modern browsers¹.

The following diagram should give you an idea of how the new heartbeat system works.

     client will disconnect
       if not recv within
          `pingTimeout`
 primus:pong:{timestamp}
+----------------------+
|                      |

+---v----+            +---------+

| server |            |  client |

+--------+            +----^----+

|                      |

+----------------------+

primus:ping:{timestamp}
  sent at `pingInterval`
  server will disconnect
  if no response since
       last ping

As you might expect there are some breaking changes.

• The latency attribute on the client is gone.
• The server-side timeout has been replaced with a new option called pingInterval.
• The client-side ping and pong options have been replaced with a new option called pingTimeout.

A special thanks goes to @STRML who assisted us in making this release possible.

1: http://blog.strml.net/2017/01/chrome-56-now-aggressively-throttles.html

Commits

The new version differs by 17 commits .

• 30d4a46 [dist] 7.0.0
• a11aaeb [minor] Move heartbeat into Spark so it can be overridden (#562)
• cfb211b [minor] Treat protocol-level pings as valid pongs
• 62b5df3 [major] Use new option names
• 3ac09f9 [major] Reverse the direction of ping/pong messages
• 52eb0f7 chore(package): update uws to version 0.14.0 (#563)
• 75da37e [test] Enable some disabled tests
• 8de2f8d chore(package): update querystringify to version 1.0.0 (#560)
• a1d1b29 [minor] Rebuild the Engine.IO client -- version 2.1.0
• 6edbcb4 chore(package): update engine.io to version 2.1.0 (#559)
• fd52a51 chore(package): update engine.io-client to version 2.1.0 (#558)
• 7d03277 chore(package): update request to version 2.81.0 (#557)
• 9c1c52f [doc] Fix indentation in code snippets (#556)
• 86de3d6 chore(package): update request to version 2.80.0 (#555)
• 01c8a09 chore(package): update ws to version 2.2.0 (#554)

There are 17 commits in total. See the full diff.

Not sure how things should work exactly?

There is a collection of frequently asked questions and of course you may always ask my humans.

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Your Greenkeeper Bot 🌴

[coveralls]

Coverage increased (+6.7%) to 98.496% when pulling c88959e on greenkeeper/primus-7.0.0 into 21037ad on master.