V1.0.3 - Images 'n stuff

Compared to the last two releases (which where kinda small) this one brings quite a lot new stuff:

• Updated SDK to 1.15.28 (if you're using nuget you already got this)
• Added an Image-Brush (if you're using nuget you already got an early version of this)
• IEnumerable-overloads for param-methods
• Improved performance of the RectangleBrush
• Added Brush-Calculation-Modes (this might brake existing brushes since the default changed. You can get the old behavior by setting it to absolute [default is relative])
• Added 4 events which allows to hook into the update-process [Updating, Updated, LedsUpdating, LedsUpdated]. (With this effects are better to use and you could even write something like shaders.)
• Added a method to check for SDK availability.

So far the documentation isn't updated - I'll need some time for this.
NuGet is of course up2date.

As always feel free to open issues if you need help or want to suggest features!