Update gulp to the latest version 🚀

The devDependency gulp was updated from `3.9.1` to `4.0.1`.

This version is not covered by your current version range.

If you don’t accept this pull request, your project will work just like it did before. However, you might be missing out on a bunch of new features, fixes and/or performance improvements from the dependency update.

Release Notes for v4.0.1

Fix

Temporary workaround for facebook/Docusaurus#257 (9f4a2e9) - Closes facebook/Docusaurus#257

Docs

Fix error in ES2015 usage example (a4e8d48) - Closes #2099 #2100
Add temporary notice for 4.0.0 vs 3.9.1 documentation (126423a) - Closes #2121
Improve recipe for empty glob array (45830cf) - Closes #2122
Reword standard to default (b065a13)
Fix recipe typo (86acdea) - Closes #2156
Add front-matter to each file (d693e49) - Closes #2109
Rename "Getting Started" to "Quick Start" & update it (6a0fa00)
Add "Creating Tasks" documentation (21b6962)
Add "JavaScript and Gulpfiles" documentation (31adf07)
Add "Working with Files" documentation (50fafc6)
Add "Async Completion" documentation (ad8b568)
Add "Explaining Globs" documentation (f8cafa0)
Add "Using Plugins" documentation (233c3f9)
Add "Watching Files" documentation (f3f2d9f)
Add Table of Contents to "Getting Started" directory (a43caf2)
Improve & fix parts of Getting Started (84b0234)
Create and link-to a "docs missing" page for LINK_NEEDED references (2bd75d0)
Redirect users to new Getting Started guides (53e9727)
Temporarily reference gulp@next in Quick Start (2cecf1e)
Fixed a capitalization typo in a heading (3d051d8) - Closes #2242
Use h2 headers within Quick Start documentation (921312c) - Closes #2241
Fix for nested directories references (4c2b9a7)
Add some more cleanup for Docusaurus (6a8fd8f)
Temporarily point LINK_NEEDED references to documentation-missing.md (df7cdcb)
API documentation improvements based on feedback (0a68710)
Update API Table of Contents (d6dd438)
Add API Concepts documentation (8dd3361)
Add Vinyl.isCustomProp() documentation (40ee801)
Add Vinyl.isVinyl() documentation (25a22bf)
Add Vinyl documentation (fc09067)
Update watch() documentation (69c22f0)
Update tree() documentation (ebb9818)
Update task() documentation (b636a9c)
Update symlink() documentation (d580efa)
Update src() documentation (d95b457)
Update series() documentation (4169cb6)
Update registry() documentation (d680487)
Update parallel() documentation (dc3cba7)
Update lastRun() documentation (363df21)
Update dest() documentation (e447d81)
Split API docs into separate markdown files (a3b8ce1)
Fix hash link (af4bd51)
Replace some links in Getting Started (c433c70)
Remove temporary workaround for facebook/Docusaurus#257 (5c07954) - Closes facebook/Docusaurus#257
Added code ticks to "null" where missing (cb67319) - Closes #2243
Fix broken link in lastRun (d35653e)
Add front-matter to documentation-missing page (a553cfd)
Improve grammar on Concepts (01cfcc5) - Closes #2247
Remove spaces around
(c960c1d)
Improve grammar in src (eb493a2) - Closes #2248
Fix formatting error (ca6ba35) - Closes #2250
Fix formatting of lastRun (8569f85) - Closes #2251
Add missing link in watch (e35bdac) - Closes #2252
Fix broken link in tasks (6d43750) - Closes #2253
Improve punctuation in tree (8e9fd70) - Closes #2254
Fix mistake in "Splitting a gulpfile" (96c353d) - Closes #2255
Remove front-matter from outdated pages (c5af6f1)
Fix broken link in Table of Contents (c641369) - Closes #2260
Update the babel dependencies to install & configuration needed (7239cf1) - Closes #2136
Add "What's new in 4.0" section (75ea634) - Closes #2089 #2267
Cleanup README for "latest" bump (24e202b) - Closes #2268
Revert "next" reference now that 4.0 is latest (ed27cbe)
Add Azure Pipelines badge (f3f0548) - Closes #2310
Add note about transpilation to "Splitting a Gulpfile" section (53b9037) - Closes #2311 #2312
Improve wording of file rename (88437f2) - Closes #2314

Upgrade

Update glob-watcher, gulp-cli, and undertaker dependencies & rimraf devDep (d3734d3)

Build

Add node 10 to CI matrices (a5eac1c)
Remove jscs & update eslint for code formatting rules (ad8a2f7)
Fix Azure comment (34a6d53) - Closes #2307
Add Azure Pipelines CI (b2c6c7e) - Closes #2299

Scaffold

Mark *.png and *.jpg as binary files to git (a010db6)
Update some links and license year (1027236)
Add tidelift configuration (49b5aca)
Add new expense policy (9819957)
Add support-bot template (9078c49)

Commits

The new version differs by 211 commits.

ea3bba4 Release: 4.0.1
d3734d3 Upgrade: Update glob-watcher, gulp-cli, and undertaker dependencies & rimraf devDep
88437f2 Docs: Improve wording of file rename (#2314)
53b9037 Docs: Add note about transpilation to "Splitting a Gulpfile" section (closes #2311) (#2312)
f3f0548 Docs: Add Azure Pipelines badge (#2310)
34a6d53 Build: Fix Azure comment (#2307)
b2c6c7e Build: Add Azure Pipelines CI (#2299)
ed27cbe Docs: Revert "next" reference now that 4.0 is latest
24e202b Docs: Cleanup README for "latest" bump (#2268)
75ea634 Docs: Add "What's new in 4.0" section (closes #2089) (#2267)
9078c49 Scaffold: Add support-bot template
7239cf1 Docs: Update the babel dependencies to install & configuration needed (closes #2136)
c641369 Docs: Fix broken link in Table of Contents (#2260)
9819957 Scaffold: Add new expense policy
c5af6f1 Docs: Remove front-matter from outdated pages

There are 211 commits in total.

See the full diff

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This change is

cinecove / defunctr