Add website to mono repo, update packages to align with existing sub-packages, use new subscribeAsync 0x.js method

packages/website/ts/components/ui/help_tooltip.tsx

@@ -0,0 +1,22 @@
+import * as React from 'react';
+import ReactTooltip = require('react-tooltip');
+
+interface HelpTooltipProps {
+    style?: React.CSSProperties;
+    explanation: React.ReactNode;
+}
+
+export const HelpTooltip = (props: HelpTooltipProps) => {
+    return (
+        <div
+            style={{...props.style}}
+            className="inline-block"
+            data-tip={props.explanation}
+            data-for="helpTooltip"
+            data-multiline={true}
+        >
+            <i style={{fontSize: 16}} className="zmdi zmdi-help" />
+            <ReactTooltip id="helpTooltip" />
+        </div>
+    );
+};