忽略内联的base64字体

[WalleV]

pull request原因：
解决font-spider误将base64内联字体当成文件路径访问导致崩溃。

抛错信息：

/Users/xxx/.nvm/versions/node/v8.0.0/bin/node /Users/.../node_modules/font-spider/bin/font-spider /Users/.../font.html
Error: "data:application/octet-stream;base64,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" file not found
    at Compress.min (/Users/.../node_modules/font-spider/src/compressor/index.js:131:29)
    at Compress.<anonymous> (/Users/.../node_modules/font-spider/src/compressor/index.js:63:22)
    at emitNone (events.js:110:20)
    at DestroyableTransform.emit (events.js:207:7)
    at /Users/.../node_modules/vinyl-fs/node_modules/readable-stream/lib/_stream_readable.js:965:16
    at _combinedTickCallback (internal/process/next_tick.js:95:7)
    at process._tickCallback (internal/process/next_tick.js:161:9)

Process finished with exit code 1

复现环境：

1. 页面引入这个css https://github.com/Tencent/weui/blob/master/dist/style/weui.css
2. 尝试压缩字体

问题根源：

• weui.css第25行携带了一个内联base64字体

解决办法：

• 在读取路径完成后将base64的路径排除掉。

测试用例：

已增加问题css到bug.css。
如果不执行base64路径过滤，会导致下面两个测试用例无法通过

1. spider html content + css content
2. spider gulp: html content + css content

执行base64路径过滤之后，测试全部通过。