refactor: switched to less for css (#49)

- Added build setup to include styles.less in building community.css
- The old styles are still in style.css. Those styles will be slowly moved to style.less.
- Move all the new styles to style.less

community/public/css/vars.css

@@ -0,0 +1,4 @@
+/* Define all your css variables here. */
+:root {
+  --primary-color: #08B74F;
+}