feat: Add react package (#4)

* chore: Organise

* feat: Add `react` package

* refactor: Remove unneeded char

packages/js/bin/build-sprite-string.js

@@ -0,0 +1,28 @@
+import DEFAULT_ATTRS from '../src/default-attrs.json';
+
+/**
+ * Build an SVG sprite string containing SVG symbols.
+ * @param {Object} icons
+ * @returns {string}
+ */
+function buildSpriteString(icons) {
+  const symbols = Object.keys(icons)
+    .map(icon => toSvgSymbol(icon, icons[icon]))
+    .join('');
+
+  return `<svg xmlns="${DEFAULT_ATTRS.xmlns}"><defs>${symbols}</defs></svg>`;
+}
+
+/**
+ * Create an SVG symbol string.
+ * @param {string} name - Icon name
+ * @param {string} contents - SVG contents
+ * @returns {string}
+ */
+function toSvgSymbol(name, contents) {
+  return `<symbol id="${name}" viewBox="${DEFAULT_ATTRS.viewBox}">${
+    contents
+  }</symbol>`;
+}
+
+export default buildSpriteString;