mod operator incorrect for decimals

[piotrszul]

FHIR R4 Exclusions

Details

Expected: true but got: false ==> expected: <true> but was: <false>

• 2.2 mod 1.8 = 0.4 [** testMod4]

[johngrimes]

We also need to update this line in the documentation:

For Integer and Decimal, +, - and * return the same type as the left operand, / returns Decimal and mod returns Integer.