missing WadRayMath helpers as needed: `dewadifyUp`, `rayToBpsDown` and `rayToBpsUp`

[DhairyaSethi]

to support #460

• WadRayMathExtended is missing the following function: dewadifyUp, rayToBpsDown and rayToBpsUp.
  • dewadifyUp can be implemented as a.wadMulUp(1), while rayToBpsUp can be implemented as a.rayMulUp(PercentageMathExtended.PERCENTAGE_FACTOR). rayToBpsDown can be implemented as a.rayMulDown(PercentageMathExtended.PERCENTAGE_FACTOR)
  • we should implement corresponding tests for the new functions