Allow optimizing over Bigfloat intervals

[ericphanson]

I looked for something like the numeric_type function I introduce here in IntervalArithmetic.jl but didn't see anything, so I just defined it here. Fixes #43.

[codecov-io]

Codecov Report

Merging #45 into master will increase coverage by 0.48%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master      #45      +/-   ##
==========================================
+ Coverage   89.06%   89.55%   +0.48%     
==========================================
  Files           4        4              
  Lines          64       67       +3     
==========================================
+ Hits           57       60       +3     
  Misses          7        7

Impacted Files	Coverage Δ
src/optimise.jl	95.23% <100%> (+0.79%)	⬆️

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[dpsanders]

LGTM, thanks a lot!

Could you please bump the version in Project.toml to 0.4.1?
(I don't know if I can edit Pull Requests myself)

[dpsanders]

Apparently you can give me permission to modify your PR like this:
https://help.github.com/en/github/collaborating-with-issues-and-pull-requests/allowing-changes-to-a-pull-request-branch-created-from-a-fork

But doesn't make sense for this particular one.

[ericphanson]

Sure, done. You won't be able to get it automerged though, since there's unbounded compat. Probably instead of e.g.

IntervalRootFinding = "≥ 0.4.0"

you want something like

IntervalRootFinding = "0.4, 0.5"

which means versions in the interval [0.4, 0.6). I'm not really sure what versions are compatible though.

[dpsanders]

Hmm. Why does this package even need IntervalRootFinding?

Anyway, could you go ahead and make that change too please?

[ericphanson]

It doesn't, nor does it seem to need IntervalConstraintProgramming. I'll try and clean up the dependencies and fix the compat.

[ericphanson]

Turns out DataStructures, ForwardDiff, IntervalConstraintProgramming, and IntervalRootFinding were all unneeded. Makes the compat much easier to figure out :)

[dpsanders]

Most of those packages are needed by various of the open PRs. But then they should be added back in in those PRs I guess!

[dpsanders]

Thanks!