Revert "added credit to the credits list"

This reverts commit 7447f5c181819ed432617ac5991886d6f505398f.
Merge pull request #28 from sergeylukin/credits

Revert "added credit to the credits list"
Add 2 credits in general project's README file
Add link to Jon Pearce's page
Merge pull request #30 from sergeylukin/credits

Add 2 credits in general project's README file
Add Gateway pattern basic overview and PHP example
Add few reasons to use gateway pattern