Rotate Texture by 90 degrees

<Google>WIKI</Google>

Because I needed a Vertical Progressbar, I had to get images of the stock Progress graphics rotate by 90 degrees. With some help from alan, this is the result.

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Texture Cache

Since we don't want to have to do this stuff everytime our plugin loads, we'll use the Texture cache.

- (BRTexture*)loadImageAndRotate:(NSString*)path
{
  NSString* cacheName = [NSString stringWithFormat:@"%iROT_%@", 
                                                 90, 
                                                 [ [path lastPathComponent] 
                                                        stringByDeletingPathExtension] ]; 
  BRTexture* texture = [[self scene] cachedTextureForKey: cacheName];