chore: remove Graphics dependency

[johnnychen94]

It's unclear why this package is added to ImageCore so maybe we should clean up this dependency. I don't plan to merge this until our next breaking release, but it's worth raising this PR to get some feedback to ensure that these are really dead codes.

This, however, does not reduce the package loading latency because the loading time is mainly due to Colors:

julia> @time_imports using ImageCore
      0.6 ms  ┌ Compat
      0.8 ms  ┌ NaNMath
      0.6 ms    ┌ Adapt
     68.4 ms    ┌ OffsetArrays
     71.9 ms  ┌ PaddedViews
   1557.8 ms      ┌ SparseArrays 4.95% compilation time
   1564.1 ms    ┌ Statistics 5.20% compilation time
   1605.8 ms  ┌ FixedPointNumbers 5.06% compilation time
     77.9 ms    ┌ ChainRulesCore
     79.9 ms  ┌ ChangesOfVariables
      9.8 ms  ┌ AbstractFFTs
      1.4 ms  ┌ OpenLibm_jll
      2.6 ms    ┌ StackViews
      3.1 ms    ┌ MappedArrays
      7.7 ms  ┌ MosaicViews
      1.1 ms  ┌ InverseFunctions
      0.4 ms  ┌ Reexport
      4.4 ms  ┌ DocStringExtensions 64.64% compilation time
     73.9 ms    ┌ ColorTypes 7.20% compilation time
    187.3 ms    ┌ Colors
    265.1 ms  ┌ Graphics 2.01% compilation time
      4.9 ms  ┌ IrrationalConstants
      0.6 ms  ┌ TensorCore
      1.1 ms    ┌ LogExpFunctions
     22.5 ms        ┌ Preferences
     23.6 ms      ┌ JLLWrappers
    227.4 ms    ┌ OpenSpecFun_jll 88.92% compilation time (99% recompilation)
    274.0 ms  ┌ SpecialFunctions 73.79% compilation time (99% recompilation)
    141.0 ms  ┌ ColorVectorSpace 4.31% compilation time
   2867.8 ms  ImageCore 10.80% compilation time (65% recompilation)

@timholy My best guess is that ImageView needed it once to share the same function names width and height with Graphics. I've manually tested that ImageView works with this branch.

@SimonDanisch Does the Makie ecosystem require this?

[codecov]

Codecov Report

Merging #185 (720b2a4) into master (6fc57c1) will decrease coverage by 0.19%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #185      +/-   ##
==========================================
- Coverage   62.67%   62.47%   -0.20%     
==========================================
  Files          10       10              
  Lines         584      581       -3     
==========================================
- Hits          366      363       -3     
  Misses        218      218              

Impacted Files	Coverage Δ
src/ImageCore.jl	72.41% <ø> (ø)
src/traits.jl	93.33% <ø> (-0.22%)	⬇️

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[SimonDanisch]

No, Makie & friends have never relied on Graphics.jl ;)

[timholy]

Graphics.jl was intended as a generic interface for graphics operations but never got to the point of actually being useful.

[timholy]

There may be some downstream failures from this, we should try to head those off quickly once this merges. But the version bump should insulate us from negative consequences.