Add a few precompiles

[timholy]

xref JuliaPlots/AbstractPlotting.jl#502

[codecov]

Codecov Report

Merging #61 into master will increase coverage by 0.08%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master      #61      +/-   ##
==========================================
+ Coverage   96.40%   96.49%   +0.08%     
==========================================
  Files           7        8       +1     
  Lines         334      342       +8     
==========================================
+ Hits          322      330       +8     
  Misses         12       12              

Impacted Files	Coverage Δ
src/MeshIO.jl	100.00% <ø> (ø)
src/precompile.jl	100.00% <100.00%> (ø)

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[timholy]

OK to merge? This eliminates quite a lot of latency (if memory serves, around 1s) in cases where it is useful.

[SimonDanisch]

Thanks a lot! :)