recursivecopy! for StaticArrays

[ranocha]

recursivecopy!now uses copy for StaticArrays, see #19. This should be correct for both mutable and immutable StaticArrays, but performance could probably be improved for mutable ones if copy! can be used.

Could you please release a new version v0.12.2 of RecursiveArrayTools including this fix?

[codecov]

Codecov Report

Merging #20 into master will increase coverage by 0.94%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master      #20      +/-   ##
==========================================
+ Coverage   61.61%   62.55%   +0.94%     
==========================================
  Files           3        3              
  Lines         211      211              
==========================================
+ Hits          130      132       +2     
+ Misses         81       79       -2

Impacted Files	Coverage Δ
src/utils.jl	46.37% <100%> (+2.89%)	⬆️

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[coveralls]

Coverage increased (+0.9%) to 62.559% when pulling 51ccc06 on ranocha:pull-request/51ccc062 into 6d304a5 on JuliaDiffEq:master.