Update ioredis to the latest version 🚀

[greenkeeper[bot]]

Version 3.0.0 of ioredis just got published.

Dependency	ioredis
Current Version	2.5.0
Type	dependency

The version 3.0.0 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 ioredis. 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

v3.0.0

Features

• pipeline: add #length to get the command count (a6060cb), closes #461
• sentinel: allow connection to IPv6-only sentinels (#463) (a389f3c)

Commits

The new version differs by 22 commits.

• 38db0cc chore(release): 3.0.0
• ddb67fc docs(CHANGELOG): 3.0.0
• b5025eb docs(README): update contributors
• a6060cb feat(pipeline): add #length to get the command count
• a389f3c feat(sentinel): allow connection to IPv6-only sentinels (#463)
• fd9a729 docs(API): remove redundant members (#462)
• e6054a3 chore(release): 3.0.0-2
• 9e750e4 docs(CHANGELOG): 3.0.0-2
• dc8256e fix: restore the default connectTimeout to 10000
• 9657213 docs: another jsdoc fix (#458)
• 4e063cb docs(API): fix jsdocs
• d1c781e chore(release): 3.0.0-1
• f83d3a2 docs(CHANGELOG): v3.0.0-1
• ce997fe docs(README): update contributors
• 626deb4 refactor: better code style for handling sentinel errors

There are 22 commits in total.

See the full diff

Not sure how things should work exactly?

There is a collection of [frequently asked questions](https://greenkeeper.io/faq.html) and of course you may always [ask my humans](https://github.com/greenkeeperio/greenkeeper/issues/new).

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Your Greenkeeper Bot :palm_tree:

[mention-bot]

@greenkeeper[bot], thanks for your PR! By analyzing the history of the files in this pull request, we identified @greenkeeper, @luoyjx and @greenkeeperio-bot to be potential reviewers.

[coveralls]

Coverage remained the same at 48.059% when pulling 2f034fca5b48fe93a7e432f8558ec86409e2d7bd on greenkeeper/ioredis-3.0.0 into 12ecedc84e85367024f5b632d4346f541aa0a9db on master.