Wavetables: Loop Points & Loop Modes

[RobDavenport]

A common feature among other samplers is to set loop points within the sample.

This means that the sound can play from beginning to end, and then afterwards loop between two designated positions. This is useful in percussive type sounds, or instruments like a piano, where the initial hit sound is unique, but if held, the long-lasting resonating sound continues to play.

I'm not sure if the end point should be configurable or not, but at least the start point should be.

We should also be able to set loop modes:

• Pure cyclic can simple go from start -> end and repeat. Like a pure sine wave.
• Loop Point should play from start -> end, and then loop between specific points within the sample. Like the piano example above.
• One-shot should play once from start -> end, and then never repeat. Like a drum.

[RobDavenport]

This was ninja-completed in #43