Add php doc.
Add php doc.

Signed-off-by: James Cole <304911e8d68d970881ef7d7c722d14b9c4899e5e@gmail.com>

tonicospinelli/firefly-iii,JC5/firefly-iii,JC5/firefly-iii,firefly-iii/firefly-iii,tonicospinelli/firefly-iii,tonicospinelli/firefly-iii,tonicospinelli/firefly-iii,firefly-iii/firefly-iii,firefly-iii/firefly-iii,firefly-iii/firefly-iii