correct folder name from `.google.` to `.google`.

[xuemind]

The folder name .google. causes error during git clone #276 in Windows file system. The folder name .google is correct one.

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[xuemind]

@googlebot I signed it!

[xuemind]

@codingjeremy Jeremy, Is is possible for you to review and approve this pull request? This issue causes failure of git clone on Windows. Thanks very much~

[xuemind]

@shailen Shailen, can you help to review and approve this fix? Thanks very much~