Hello!

Just saw #199 but as it has no content, plus it contains multiple issues, I thought I'd write this up.

I'm very new to this library, but it seems great and mostly covers everything I need. However, I'm trying to add transparency to fill colour. Looking at the code, it seems like it's using ARGB (and in the Color class handles ARGB channels), however in the saved out presentation, it seems to always use a 100% alpha channel.

Taking the Linear gradient example from the samples directory the following code makes the background a gradient;

$shape->getFill()->setFillType(Fill::FILL_GRADIENT_LINEAR)->setRotation(90)->setStartColor(new Color( 'FF4672A8' ))->setEndColor(new Color( 'FF000000' ));

I assumed by changing the prefixing FF (alpha channel) that this would just work but it appears not. Is there anything special needed to get Alpha transparency to work?

Thanks for all your hard work!