Fixes for Julia 0.7 and 1.0

[simonschoelly]

Not sure how much this package is still maintained. But this pr should make it work with Julia 0.7 and 1.0 again.

[codecov-io]

Codecov Report

Merging #13 into master will decrease coverage by 3.84%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master      #13      +/-   ##
==========================================
- Coverage     100%   96.15%   -3.85%     
==========================================
  Files           1        1              
  Lines          53       52       -1     
==========================================
- Hits           53       50       -3     
- Misses          0        2       +2

Impacted Files	Coverage Δ
src/StructsOfArrays.jl	96.15% <100%> (-3.85%)	⬇️

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[piever]

The same functionality of this packages is available on StructArrays which works on julia 1.0.

[simonschoelly]

Yes, (I think we did discussed that on slack before), we should get StructOfArrays into JuliaArrays and deprecate this package.