Create Kokoro TTS JavaScript library (#3)

* Set up JS project

* Finalise JS library

* Update README

* Fix package.json repository url

* Rename package -> `kokoro-js`

* Fix samples in README

* Cleanup README

* Bump `phonemizer` version

* Create web demo

* Run prettier

* Link to model used in demo

* Enable multithreading in HF space demo (~40% faster)

* Add link to demo in README

* Bump to v1.0.1

kokoro.js/demo/public/wave.svg

@@ -0,0 +1,9 @@
+<svg xmlns="http://www.w3.org/2000/svg" width="1600" height="198">
+  <defs>
+    <linearGradient id="a" x1="50%" x2="50%" y1="-10.959%" y2="100%">
+      <stop stop-color="#57BBC1" stop-opacity=".25" offset="0%"/>
+      <stop stop-color="#015871" offset="100%"/>
+    </linearGradient>
+  </defs>
+  <path fill="url(#a)" fill-rule="evenodd" d="M.005 121C311 121 409.898-.25 811 0c400 0 500 121 789 121v77H0s.005-48 .005-77z" transform="matrix(-1 0 0 1 1600 0)"/>
+</svg>