Specify which browsers we support to remove some Babel transforms

[captbaritone]

eel-wasm makes heavy use of the ... array spread operator and the native version performs much better than the transformed version. I suspect this will also decrease the bundle size.

Before

Using targets:
{}

Using modules transform: auto

Using plugins:
  proposal-numeric-separator {}
  proposal-logical-assignment-operators {}
  proposal-nullish-coalescing-operator {}
  proposal-optional-chaining {}
  proposal-json-strings {}
  proposal-optional-catch-binding {}
  transform-parameters {}
  proposal-async-generator-functions {}
  proposal-object-rest-spread {}
  transform-dotall-regex {}
  proposal-unicode-property-regex {}
  transform-named-capturing-groups-regex {}
  transform-async-to-generator {}
  transform-exponentiation-operator {}
  transform-template-literals {}
  transform-literals {}
  transform-function-name {}
  transform-arrow-functions {}
  transform-block-scoped-functions {}
  transform-classes {}
  transform-object-super {}
  transform-shorthand-properties {}
  transform-duplicate-keys {}
  transform-computed-properties {}
  transform-for-of {}
  transform-sticky-regex {}
  transform-unicode-escapes {}
  transform-unicode-regex {}
  transform-spread {}
  transform-destructuring {}
  transform-block-scoping {}
  transform-typeof-symbol {}
  transform-new-target {}
  transform-regenerator {}
  transform-member-expression-literals {}
  transform-property-literals {}
  transform-reserved-words {}
  proposal-export-namespace-from {}
  syntax-dynamic-import {}
  syntax-top-level-await {}

After

Using targets:
{
  "android": "81",
  "chrome": "65",
  "edge": "79",
  "firefox": "59",
  "opera": "52",
  "samsung": "7.2"
}

Using modules transform: auto

Using plugins:
  proposal-numeric-separator { "chrome":"65", "firefox":"59", "opera":"52", "samsung":"7.2" }
  proposal-logical-assignment-operators { "android":"81", "chrome":"65", "edge":"79", "firefox":"59", "opera":"52", "samsung":"7.2" }
  proposal-nullish-coalescing-operator { "chrome":"65", "edge":"79", "firefox":"59", "opera":"52", "samsung":"7.2" }
  proposal-optional-chaining { "chrome":"65", "edge":"79", "firefox":"59", "opera":"52", "samsung":"7.2" }
  proposal-json-strings { "chrome":"65", "firefox":"59", "opera":"52", "samsung":"7.2" }
  proposal-optional-catch-binding { "chrome":"65", "opera":"52", "samsung":"7.2" }
  proposal-async-generator-functions { "samsung":"7.2" }
  proposal-object-rest-spread { "samsung":"7.2" }
  transform-dotall-regex { "firefox":"59", "samsung":"7.2" }
  proposal-unicode-property-regex { "firefox":"59", "samsung":"7.2" }
  transform-named-capturing-groups-regex { "firefox":"59", "samsung":"7.2" }
  proposal-export-namespace-from { "chrome":"65", "firefox":"59", "opera":"52", "samsung":"7.2" }
  syntax-dynamic-import { "android":"81", "chrome":"65", "edge":"79", "firefox":"59", "opera":"52", "samsung":"7.2" }
  syntax-top-level-await { "android":"81", "chrome":"65", "edge":"79", "firefox":"59", "opera":"52", "samsung":"7.2" }

[captbaritone]

Size Change: -4.49 kB (-7%) ✅

Total Size: 64.4 kB

Filename	Size	Change
./dist/butterchurn.min.js	63.8 kB	-4.5 kB (-7%)	✅
./dist/isSupported.min.js	678 B	+8 B (+1%)

[captbaritone]

Same idea applied to Webamp: captbaritone/webamp#1069