Inform people how to get homebrew-php
minor #273 Inform people how to get homebrew-php (webchickenator)

This PR was merged into the 0.4.x-dev branch.

Discussion
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Inform people how to get homebrew-php

When I followed the brew installation instructions, I received the error:

"php-cs-fixer: Missing PHP53, PHP54 or PHP55 from homebrew-php. Please install one of them before continuing"

But, there was no info on how to get that. Adding a section to the README, though ideally this error message would contain it. (I wasn't able to find this string in the source, though.)

Commits
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9c3bc96 Inform people how to get homebrew-php
updated README