php-protobuf code
Removed examples and tests
Make it compile with PHP 5.3
php-protobuf had the same bug with empty comments as pb4php...
Fixed problem with nested messages if there were multiple ones.
Add PB_ prefix to enums
Removed old protobuf code
First try at using php-protobuf
All tests are passing :-)
Revert "Removed old protobuf code"

This reverts commit 5db23b6b51ee7b280f54a9dbe187c7b5dcdd6531.
Support multiple protobuf backends.

Closes #22.
Add PHP namespace support to php-protobuf compiler.

Closes #23.