added test of RGB int input decorator
added test of RGB int input decorator

Three cases tested:
1. input base dtype doesn't match, input is scaled up to [0,255] interval
2. input base dtype matches, but exact type doesn't, so it's converted to a uint8
3. input base dtype matches and the exact dtype matches, so nothing happens to the input array

TadLeonard/husl-numpy,TadLeonard/husl-numpy,TadLeonard/husl-numpy