chore: bump dev dependencies to resolve install warnings

[nfischer]

This bumps several dev dependencies to avoid depending on deprecated packages.
This also adds package-lock.json to eliminate those warnings and the hassle
involved with constantly removing the uncommitted file.

Issue #134

[nfischer]

For comparison, here's what a fresh install looks like after this PR:

$ rm -rf node_modules/
$ npm install

npm WARN prepublish-on-install As of npm@5, `prepublish` scripts are deprecated.
npm WARN prepublish-on-install Use `prepare` for build steps and `prepublishOnly` for upload-only.
npm WARN prepublish-on-install See the deprecation note in `npm help scripts` for more information.

> shx@0.3.0 prepublish [path redacted]/shx
> npm run build


> shx@0.3.0 prebuild [path redacted]/shx
> rimraf lib


> shx@0.3.0 build [path redacted]/shx
> babel src -d lib

src/cli.js -> lib/cli.js
src/config.js -> lib/config.js
src/help.js -> lib/help.js
src/printCmdRet.js -> lib/printCmdRet.js
src/shx.js -> lib/shx.js
added 649 packages in 13.346s

[codecov-io]

Codecov Report

Merging #135 into master will not change coverage.
The diff coverage is n/a.

@@          Coverage Diff          @@
##           master   #135   +/-   ##
=====================================
  Coverage     100%   100%           
=====================================
  Files           3      4    +1     
  Lines          25     68   +43     
=====================================
+ Hits           25     68   +43

Impacted Files	Coverage Δ
src/shx.js	100% <0%> (ø)	⬆️
src/printCmdRet.js	100% <0%> (ø)	⬆️
src/config.js	100% <0%> (ø)	⬆️
src/help.js	100% <0%> (ø)

---

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[nfischer]

The coverage change looks like a bug with nyc, not with codecov. Seems like the bug got introduced around nyc v7.0.0.

[nfischer]

And I think v10.0.0 introduced a change where config.js:47 is also marked as uncovered:

----------------|----------|----------|----------|----------|----------------|
File            |  % Stmts | % Branch |  % Funcs |  % Lines |Uncovered Lines |
----------------|----------|----------|----------|----------|----------------|
All files       |    98.53 |    93.94 |      100 |    98.44 |                |
 config.js      |      100 |    88.89 |      100 |      100 |             47 |
 help.js        |      100 |      100 |      100 |      100 |                |
 printCmdRet.js |      100 |      100 |      100 |      100 |                |
 shx.js         |    97.62 |    93.75 |      100 |    97.44 |            100 |
----------------|----------|----------|----------|----------|----------------|

[freitagbr]

LGTM

[nfischer]

Newsflash! The new nyc version is not buggy--those were real coverage issues. Uploaded #139 to fix those (and marking this as blocked by that PR).