Support differentiating trigonometric functions.
Support differentiating trigonometric functions.

Spot-checked against Wolfram Alpha for a few examples, such as:
- sin (x ** 2)
- sin x / x
- asin (x ** 2)

GaloisInc/ivory-tower-stm32,GaloisInc/ivory-tower-stm32,GaloisInc/ivory-tower-stm32