XNAExtras build 0923 release

Major addition for this version: collision detection has been added to XSpriteManager. Both bounding box and pixel based (mix-n-match sprites of different types). Also boundary collisions. These are demoed in the bouncy CollisionDemo example:

From the release notes:

(BMFontGen) Fixed bug where including undefined chars in your font -range would cause a crash
(BitmapFont) Changed loading embedded resources - now the resource name is specified in the same format as file-based resources
(BitmapFont) Fixed bug where font files wouldn't be found unless they were in a subdirectory
(TextBox) Added accessors for the text string
(XSpriteManager) Changed default FPS to 60
(XSpriteManager) Added support for collisions
(TexturePool) *Really* fixed bug in AddTexture(string,Color) where the texture wasn't being created if the GraphicsDevice already existed - the fix got lost for the last release

Thanks to redwyre, David Zakar (DMZ), Martin Szinger and Matt Moore for comments/suggestions.

You can download the 0923 build of XNAExtras here.