fix(deps): update dependency yargs to v15

[renovate-bot]

This PR contains the following updates:

Package	Type	Update	Change
yargs (source)	dependencies	major	^14.0.0 -> ^15.0.0

---

Release Notes

yargs/yargs

### [`v15.0.1`](https://togithub.com/yargs/yargs/blob/master/CHANGELOG.md#​1501httpswwwgithubcomyargsyargscomparev1500v1501-2019-11-16) [Compare Source](https://togithub.com/yargs/yargs/compare/v15.0.0...v15.0.1) ### [`v15.0.0`](https://togithub.com/yargs/yargs/blob/master/CHANGELOG.md#​1500httpswwwgithubcomyargsyargscomparev1420v1500-2019-11-10) [Compare Source](https://togithub.com/yargs/yargs/compare/2fe88f5e224ef495c9c03a85fde29b2ae44f5c54...v15.0.0) ##### ⚠ BREAKING CHANGES - **deps:** yargs-parser now throws on invalid combinations of config ([#​1470](https://togithub.com/yargs/yargs/issues/1470)) - yargs-parser@16.0.0 drops support for Node 6 - drop Node 6 support ([#​1461](https://togithub.com/yargs/yargs/issues/1461)) - remove package.json-based parserConfiguration ([#​1460](https://togithub.com/yargs/yargs/issues/1460)) ##### Features - **deps:** yargs-parser now throws on invalid combinations of config ([#​1470](https://www.github.com/yargs/yargs/issues/1470)) ([c10c38c](https://www.github.com/yargs/yargs/commit/c10c38cca04298f96b55a7e374a9a134abefffa7)) - expose `Parser` from `require('yargs/yargs')` ([#​1477](https://www.github.com/yargs/yargs/issues/1477)) ([1840ba2](https://www.github.com/yargs/yargs/commit/1840ba22f1a24c0ece8e32bbd31db4134a080aee)) ##### Bug Fixes - **docs:** TypeScript import to prevent a future major release warning ([#​1441](https://www.github.com/yargs/yargs/issues/1441)) ([b1b156a](https://www.github.com/yargs/yargs/commit/b1b156a3eb4ddd6803fbbd56c611a77919293000)) - stop-parse was not being respected by commands ([#​1459](https://www.github.com/yargs/yargs/issues/1459)) ([12c82e6](https://www.github.com/yargs/yargs/commit/12c82e62663e928148a7ee2f51629aa26a0f9bb2)) - update to yargs-parser with fix for array default values ([#​1463](https://www.github.com/yargs/yargs/issues/1463)) ([ebee59d](https://www.github.com/yargs/yargs/commit/ebee59d9022da538410e69a5c025019ed46d13d2)) - **docs:** update boolean description and examples in docs ([#​1474](https://www.github.com/yargs/yargs/issues/1474)) ([afd5b48](https://www.github.com/yargs/yargs/commit/afd5b4871bfeb90d58351ac56c5c44a83ef033e6)) ##### Miscellaneous Chores - drop Node 6 support ([#​1461](https://www.github.com/yargs/yargs/issues/1461)) ([2ba8ce0](https://www.github.com/yargs/yargs/commit/2ba8ce05e8fefbeffc6cb7488d9ebf6e86cceb1d)) ##### Code Refactoring - remove package.json-based parserConfiguration ([#​1460](https://www.github.com/yargs/yargs/issues/1460)) ([0d3642b](https://www.github.com/yargs/yargs/commit/0d3642b6f829b637938774c0c6ce5f6bfe1afa51))

---

Renovate configuration

:date: Schedule: "after 9am and before 3pm" (UTC).

:vertical_traffic_light: Automerge: Disabled by config. Please merge this manually once you are satisfied.

:recycle: Rebasing: Whenever PR is stale, or if you modify the PR title to begin with "rebase!".

:no_bell: Ignore: Close this PR and you won't be reminded about this update again.

---

• [ ] If you want to rebase/retry this PR, check this box

---

Newsflash: Renovate has joined WhiteSource, and is now free for all use. Learn more or view updated terms and privacy policies.

[codecov[bot]]

Codecov Report

Merging #377 into master will not change coverage. The diff coverage is n/a.

@@          Coverage Diff           @@
##           master    #377   +/-   ##
======================================
  Coverage    97.1%   97.1%           
======================================
  Files           2       2           
  Lines         449     449           
  Branches       37      37           
======================================
  Hits          436     436           
  Misses         13      13

---

Continue to review full report at Codecov.

Legend - Click here to learn more Δ = absolute <relative> (impact), ø = not affected, ? = missing data Powered by Codecov. Last update 285cf33...95cee54. Read the comment docs.