Support mixed argument types to div and friends

[Tokazama]

This simply makes it so that when something like div(9m, 3) it produces 3m. Currently this errors instead.

[codecov-io]

Codecov Report

Merging #317 into master will decrease coverage by 2.65%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #317      +/-   ##
==========================================
- Coverage   81.39%   78.74%   -2.66%     
==========================================
  Files          15       15              
  Lines        1129     1129              
==========================================
- Hits          919      889      -30     
- Misses        210      240      +30

Impacted Files	Coverage Δ
src/quantities.jl	92.74% <100%> (-0.31%)	⬇️
src/range.jl	57.14% <0%> (-26.2%)	⬇️
src/units.jl	77.61% <0%> (-8.96%)	⬇️
src/types.jl	89.36% <0%> (-4.26%)	⬇️
src/dimensions.jl	91.89% <0%> (-2.71%)	⬇️
src/logarithm.jl	65.47% <0%> (-1.35%)	⬇️
src/user.jl	94.85% <0%> (-0.19%)	⬇️
src/display.jl	96% <0%> (-0.08%)	⬇️

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[Tokazama]

I've also added a version bump for a patch release. Hope that's okay

[Wikunia]

I just had a look at div again and it has a third parameter.

  julia> div(4, 3, RoundDown) # Matches fld(4, 3)
  1
  julia> div(4, 3, RoundUp) # Matches cld(4, 3)
  2
  julia> div(5, 2, RoundNearest)
  2
  julia> div(5, 2, RoundNearestTiesAway)
  3
  julia> div(-5, 2, RoundNearest)
  -2
  julia> div(-5, 2, RoundNearestTiesAway)
  -3
  julia> div(-5, 2, RoundNearestTiesUp)
  -2

You might want to have this supported as well.

[Tokazama]

Good, point. The other thing is that in more recent versions of Julia we are only suppose to overload div and other operators are suppose to follow. I'm not sure if I should be addressing this too.

[Wikunia]

unit(y) is a free unit so it is just unit(x) isn't it?

[Tokazama]

You're correct. I was just copying the / method above. I'll fix it.

[Tokazama]

Not sure why this worked for me on 1.4 but is broken on everything earlier. I'll look at it more later today.

[Wikunia]

The feature I meant with the rounding mode is supported since 1.4 as far as I can see.

[Wikunia]

Not sure how to deal with it maybe @giordano can help. You probably want to support Julia 1.0.
Is this something for Compat?

[giordano]

I'd do

Suggested change

	function div(x::AbstractQuantity, y::AbstractQuantity, r::RoundingMode=RoundToZero)
	z = uconvert(unit(y), x) # TODO: use promote?
	div(z.val,y.val, r)
	end
	function div(x::AbstractQuantity, y::AbstractQuantity, r...)
	z = uconvert(unit(y), x) # TODO: use promote?
	div(z.val,y.val, r...)
	end

so you don't even have to care to forcibly set a default value

[Tokazama]

That sounds better than my idea.

[Tokazama]

Oh, then I just need to put the div code with the extra parameter inside a `if VERSION > v"1.3"`` block.