Added browser field as hint for JS bundlers

[nickedelenbos]

Some JS bundlers prefer to have a specific browser key in the package.json file, in order to bundle files efficiently (as can be read at https://github.com/defunctzombie/package-browser-field-spec). This PR adds the browser/float16.js as main entry point in that field

[petamoriken]

IMHO, browser field is outdated and I recommend to use src directory for bundlers for tree shaking. Maybe modern bundlers use import field instead. Please show me which bundler uses browser field efficiently.

[nickedelenbos]

@petamoriken Liferay NPM bundler does this; https://help.liferay.com/hc/en-us/articles/360017880812-Configuring-liferay-npm-bundler

[petamoriken]

@nickedelenbos

I didn't know liferay-npm-bundler.

Liferay NPM bundler does this; https://help.liferay.com/hc/en-us/articles/360017880812-Configuring-liferay-npm-bundler

I couldn't find about browser field in package.json from this document. Please tell me problems that this PR will solve specially.

[codecov]

Codecov Report

Merging #589 (751c34b) into master (8d48c8c) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #589   +/-   ##
=======================================
  Coverage   88.03%   88.03%           
=======================================
  Files          12       12           
  Lines         727      727           
  Branches      137      137           
=======================================
  Hits          640      640           
  Misses         43       43           
  Partials       44       44           

Flag	Coverage Δ
unittests	88.03% <ø> (ø)

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[nickedelenbos]

@petamoriken By default applications will look, as specified in https://docs.npmjs.com/cli/v8/configuring-npm/package-json#main, to the main key in the package.json. This main fields points to CommonJS modules, typically used in server side libraries. My PR proposes to add a browser field, which is typically used by client-side (browser) applications to resolve the library.

[petamoriken]

Make sense.