Consider adding support for unit when using math.round()

[mofosyne]

First example works as expected

math.round(math.evaluate("2.223"), 2).toString()
"2.22"

Second example doesn't work as expected

math.round(math.evaluate("2.223kg"), 2).toString() 
Uncaught TypeError: Unexpected type of argument in function round (expected: number or Complex or BigNumber or Fraction or Array or Matrix or DenseMatrix or SparseMatrix or string or boolean, actual: Unit, index: 0)

My desired behavior would be

math.round(math.evaluate("2.223kg"), 2).toString()
"2.22kg"

Possible challenges, is you will need to account for people doing strange units like "kg2.223" or "2.223kg^2", so addressing this will require parsing to properly capture the units.

[josdejong]

I think this is a duplicate of #2761, let's continue the discussion there.

[mofosyne]

Ah missed that as I was only searching issue tickets. Thanks