Control significant digits in VegaLite plot tooltips

[pablosanjose]

vlplot(h::Hamiltonian, digits = 5) is the default.

[codecov-commenter]

Codecov Report

Merging #102 into master will not change coverage.
The diff coverage is 0.00%.

@@           Coverage Diff           @@
##           master     #102   +/-   ##
=======================================
  Coverage   62.00%   62.00%           
=======================================
  Files          16       16           
  Lines        2682     2682           
=======================================
  Hits         1663     1663           
  Misses       1019     1019           

Impacted Files	Coverage Δ
src/plot_vegalite.jl	0.00% <0.00%> (ø)
src/tools.jl	56.70% <0.00%> (ø)

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