trafficserver pull request: Fix a typo

[bellofreedom]

GitHub user bellofreedom opened a pull request:

    https://github.com/apache/trafficserver/pull/29

    Fix a typo

    

You can merge this pull request into a Git repository by running:

    $ git pull https://github.com/bellofreedom/trafficserver patch-1

Alternatively you can review and apply these changes as the patch at:

    https://github.com/apache/trafficserver/pull/29.patch

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commit 15491d6c7f2dbd3bef78ae0228043a6dadb2e129
Author: bellofreedom <lk130...@gmail.com>
Date:   2014-01-03T02:44:52Z

    Update security-options.en.rst
    
    Fix typo

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