Exclude by include path

this PR to proof of concept relative to #41 and #88. I try to have as few changes as possible. I changed:

- include(base) options added.  User can add their include(base) element html(s) as list. like this:

```
vulcanize -o src/build.html src/index.html -i src/base-vulcanize.html -i src/base-vulcanize2.html --config src/vulcanize.json --verbose
```

- [Exclude patterns come from polymer-element's name and assetpath](https://github.com/ragingwind/vulcanize/compare/exclude-by-include?expand=1#diff-e50d31c5b9c4a6ff6f726db454efa588R105) to exclude.import list
- I updated sample file name in test that changed simple-import to my-element. Because If there is mismatched between filename and polymer-element's name It wouldn't work properly see above.

Here is my test htmls:

```
## elements/base.html => elements/base-vulcanize.html
<link rel="import" href="../components/core-scaffold/core-scaffold.html">
<link rel="import" href="../components/core-toolbar/core-toolbar.html">
<link rel="import" href="../components/core-header-panel/core-header-panel.html">
<link rel="import" href="../components/core-menu/core-menu.html">
<link rel="import" href="../components/core-item/core-item.html">
<link rel="import" href="../components/core-iconset-svg/core-iconset-svg.html">
<link rel="import" href="../components/core-menu-button/core-menu-button.html">

## elements/app-main.html
<link rel="import" href="base-vulcanize.html">
<!-- duplicated to base.html -->
<link rel="import" href="../components/core-scaffold/core-scaffold.html">
<link rel="import" href="../components/core-toolbar/core-toolbar.html">
<link rel="import" href="../components/core-header-panel/core-header-panel.html">
<link rel="import" href="../components/core-menu/core-menu.html">
<link rel="import" href="../components/core-item/core-item.html">
<link rel="import" href="../components/core-iconset-svg/core-iconset-svg.html">
<link rel="import" href="../components/core-menu-button/core-menu-button.html">

<polymer-element name="app-main">
<template>
  <style>
  .content {
    padding: 20px;
  }
  core-item[icon="polymer"] {
    color: #a4c639;
  }
  </style>
  <core-scaffold responsiveWidth="1024px">
  <core-header-panel navigation flex>
    <core-toolbar>Menu</core-toolbar>
    <core-menu>
      <core-item icon="home" label="Home"></core-item>
      <core-item icon="account-box" label="Profile"></core-item>
      <core-item icon="settings" label="Settings"></core-item>
    </core-menu>
  </core-header-panel>
    <div tool>Drawer-Content App</div>
    <div fit class="content">
      Alo, Alo
    </div>
  </core-scaffold>
</template>
<script src="app-main.js"></script>
</polymer-element>

## index.html
<!doctype html>
<html>
<head>
  <title>Chrome apps with Polymer</title>
  <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
  <script src="components/webcomponentsjs/webcomponents.js"></script>
</head>
<link rel="import" href="elements/app-main.html">
<body unresolved="" touch-action="auto">
  <app-main></app-main>
</body>
</html>
```

and tested with:
```
# make a base html
vulcanize -o src/elements/base-vulcanize.html src/elements/base.html

# build application
vulcanize -o src/build.html src/index.html -i src/elements/base-vulcanize.html --config src/vulcanize.json --verbose
```

Thanks. Please let me know what is your opinions, any suggestion or I missed.