add loading PhpLexer
minor#6 add loading PhpLexer (dbu)

This PR was merged into the master branch.

Discussion
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add loading PhpLexer

i got an error on undefined PhpLexer and realized the symfony doc was updated but not this readme: http://symfony.com/doc/current/contributing/documentation/format.html#installing-the-sphinx-extensions

Commits
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5302de1 add loading PhpLexer