Merge pull request #515 from shoutem/release/4.0.0

Introducing SVG icons:
* Icon component now uses SVG icons instead of font icons
* Existing set of font icons is replaced with new SVG icons
* Users are allowed to add/register custom icons to existing set

Set this as a breaking change since font icons are now deprecated.

components/Icon/Icon.js

@@ -0,0 +1,34 @@
+import React from "react";
+import PropTypes from "prop-types";
+import _ from "lodash";
+import { connectStyle } from "@shoutem/theme";
+import { getIcon } from "./services";
+
+function Icon({ name, style, ...otherProps }) {
+  const { color, width, height, ...otherStyle } = style;
+
+  const Icon = getIcon(name);
+
+  if (!Icon) {
+    console.warn(`Icon with ${name} name not found within the provided set`);
+
+    return null;
+  }
+
+  return (
+    <Icon
+      fill={color}
+      width={width}
+      height={height}
+      style={{ ...otherStyle }}
+      {...otherProps}
+    />
+  );
+}
+
+Icon.propTypes = {
+  name: PropTypes.string.isRequired,
+  style: PropTypes.any,
+};
+
+export default connectStyle("shoutem.ui.Icon")(Icon);