Update gulp-sourcemaps to version 2.2.1 🚀

[greenkeeperio-bot]

Hello lovely humans,

gulp-sourcemaps just published its new version 2.2.1.

State	Update 🚀
Dependency	gulp-sourcemaps
New version	2.2.1
Type	devDependency

This version 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 gulp-sourcemaps.
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.

Do you have any ideas how I could improve these pull requests? Did I report anything you think isn’t right?
Are you unsure about how things are supposed to work?

There is a collection of frequently asked questions and while I’m just a bot, there is a group of people who are happy to teach me new things. Let them know.

Good luck with your project ✨

You rock!

🌴

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The new version differs by 100 commits .

• e207533 Bump to 2.2.1 for pre-release
• ba930bd Merge branch '1.X'
• 66e6d2a Merge pull request #255 from realtymaps/dev/nem/1.X/preExistingSourcemapFlag
• b7f1dbf fix comment
• 970cb95 test only LTS node
• 1a437f7 fix for crappy 0.10.X node
• 6972337 preExisting sourceMapping checks to not modify the original file
• 25f5778 .gitignore for *.lock for people using yarn
• ec9b51d Merge branch '1.X': Bumped to 2.2.X for engines >=4
• 0290827 bumping to 1.9.X for engines def
• 6aa5eb4 Merge branch '1.X'
• 3f76e4b changed file creation which was shallow cloning anyways to use clone always with deep:false, and contents: false
• 4bb8d2d Merge cherry-pick
• 675ef67 .gitignore
• bfd155b Adds an clone options to gulp-sourcemaps.write()

There are 100 commits in total. See the full diff.

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This pull request was created by greenkeeper.io.

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