Close #483

* Fixed precision of GiB indicated values
* Fixed three-level dot grid display not working as intended, it now show correctly cache, active and free mem slots
* Added swap monitoring for all OSs

* nanoid-generated identifiers
* list of modals are stored in an object rather than an array
* clicking or touching a modal window will bring it to the top, emulating common window managers behavior

...with node-gyp and make(2)

Bumps [howler](https://github.com/goldfire/howler.js) from 2.1.1 to 2.1.2.
- [Release notes](https://github.com/goldfire/howler.js/releases)
- [Changelog](https://github.com/goldfire/howler.js/blob/master/CHANGELOG.md)
- [Commits](https://github.com/goldfire/howler.js/compare/v2.1.1...v2.1.2)
Signed-off-by: Ndependabot[bot] <support@dependabot.com>

Bumps [systeminformation](https://github.com/sebhildebrandt/systeminformation) from 4.1.4 to 4.1.5.
- [Release notes](https://github.com/sebhildebrandt/systeminformation/releases)
- [Changelog](https://github.com/sebhildebrandt/systeminformation/blob/master/CHANGELOG.md)
- [Commits](https://github.com/sebhildebrandt/systeminformation/commits)
Signed-off-by: Ndependabot[bot] <support@dependabot.com>

Fix second tab visually broken #464

Close #464

See reason/explanation in snyk policy file.

https://app.snyk.io/vuln/SNYK-JS-TAR-174125

Bumps [xterm](https://github.com/xtermjs/xterm.js) from 3.12.0 to 3.12.2.
<details>
<summary>Release notes</summary>

*Sourced from [xterm's releases](https://github.com/xtermjs/xterm.js/releases).*

> ## 3.12.2
> ## 🐞 Bug fixes
> 
> - Published missing `dist/` directory ([#2013](https://github-redirect.dependabot.com/xtermjs/xterm.js/issues/2013)) via [@&#8203;Tyriar](https://github.com/Tyriar)
> 
> ## 3.12.1
> ## 🐞 Bug fixes
> 
> - Fix crash related to reflowing wrapped lines ending that ended in `\t` ([#2010](https://github-redirect.dependabot.com/xtermjs/xterm.js/issues/2010)) via [@&#8203;Tyriar](https://github.com/Tyriar)
</details>
<details>
<summary>Commits</summary>

- [`51d0412`](https://github.com/xtermjs/xterm.js/commit/51d04125efb724c57fb50f72d12a36e8ae64c2c6) v3.12.2
- [`d936a81`](https://github.com/xtermjs/xterm.js/commit/d936a81c1f3ee11800f51cfefbf20ff44ddf0253) Merge pull request [#2011](https://github-redirect.dependabot.com/xtermjs/xterm.js/issues/2011) from xtermjs/Tyriar-patch-1
- [`14a065e`](https://github.com/xtermjs/xterm.js/commit/14a065e7c04e3bd60bede18195af66a405df640f) v3.12.1
- [`3ad45b7`](https://github.com/xtermjs/xterm.js/commit/3ad45b72b6d1cb816af101f5cf7deb2d95c1cd89) Merge pull request [#2010](https://github-redirect.dependabot.com/xtermjs/xterm.js/issues/2010) from Tyriar/3.12.1_1932_reflow
- [`925cdae`](https://github.com/xtermjs/xterm.js/commit/925cdaef6751dec635935e03b6309d6049e7728e) Fix reflow larger case
- [`fa2a32e`](https://github.com/xtermjs/xterm.js/commit/fa2a32e43164c8a9cf69df18201220ce463ad89e) Fix reflow smaller case related to ended \t chars
- See full diff in [compare view](https://github.com/xtermjs/xterm.js/compare/3.12.0...3.12.2)
</details>
<br />

[![Dependabot compatibility score](https://api.dependabot.com/badges/compatibility_score?dependency-name=xterm&package-manager=npm_and_yarn&previous-version=3.12.0&new-version=3.12.2)](https://dependabot.com/compatibility-score.html?dependency-name=xterm&package-manager=npm_and_yarn&previous-version=3.12.0&new-version=3.12.2)

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(in build system, packaged and installed apps not affected)

Bumps [electron](https://github.com/electron/electron) from 4.1.1 to 4.1.3.
- [Release notes](https://github.com/electron/electron/releases)
- [Commits](https://github.com/electron/electron/compare/v4.1.1...v4.1.3)
Signed-off-by: Ndependabot[bot] <support@dependabot.com>

Bumps [systeminformation](https://github.com/sebhildebrandt/systeminformation) from 4.1.3 to 4.1.4.
- [Release notes](https://github.com/sebhildebrandt/systeminformation/releases)
- [Changelog](https://github.com/sebhildebrandt/systeminformation/blob/master/CHANGELOG.md)
- [Commits](https://github.com/sebhildebrandt/systeminformation/commits)
Signed-off-by: Ndependabot[bot] <support@dependabot.com>

Bumps [ws](https://github.com/websockets/ws) from 6.2.0 to 6.2.1.
- [Release notes](https://github.com/websockets/ws/releases)
- [Commits](https://github.com/websockets/ws/compare/6.2.0...6.2.1)
Signed-off-by: Ndependabot[bot] <support@dependabot.com>

⬆️ Bump systeminformation from 4.1.1 to 4.1.3 in /src