update elements and fix some bugs

lib/src/paper-styles/paper-styles.html

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 @license
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 This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
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 <link rel="import" href="../iron-flex-layout/iron-flex-layout.html">
 <link rel="import" href="../iron-flex-layout/classes/iron-flex-layout.html">
 
+<!--
+The `<paper-styles>` component provides simple ways to use Material Design CSS styles
+in your application. The following imports are available:
+
+1. [color.html](https://github.com/PolymerElements/paper-styles/blob/master/color.html):
+a complete list of the colors defined in the Material Design [palette](https://www.google.com/design/spec/style/color.html)
+
+2. [default-theme.html](https://github.com/PolymerElements/paper-styles/blob/master/default-theme.html): text,
+background and accent colors that match the default Material Design theme
+
+3. [shadow.html](https://github.com/PolymerElements/paper-styles/blob/master/shadow.html): Material Design
+[elevation](https://www.google.com/design/spec/what-is-material/elevation-shadows.html) and shadow styles
+
+4. [typography.html](https://github.com/PolymerElements/paper-styles/blob/master/typography.html):
+Material Design [font](http://www.google.com/design/spec/style/typography.html#typography-styles) styles and sizes
+
+5. [demo-pages.html](https://github.com/PolymerElements/paper-styles/blob/master/demo-pages.html): generic styles
+used in the PolymerElements demo pages
+
+@group Iron Elements
+@pseudoElement paper-styles
+@demo demo/index.html
+-->
+
 <link rel="import" href="color.html">
 <link rel="import" href="default-theme.html">
 <link rel="import" href="shadow.html">
 <link rel="import" href="typography.html">