Typedef for union. Fixes #475, #496, #508, #522, #524 and #556

[Konstantin8105]

Close #475
Close #524
Close #522
Close #508
Close #496
Close #556

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This change is 

[codecov]

Codecov Report

Merging #523 into master will decrease coverage by 0.42%.
The diff coverage is 84.61%.

@@            Coverage Diff             @@
##           master     #523      +/-   ##
==========================================
- Coverage   80.46%   80.04%   -0.43%     
==========================================
  Files         156      156              
  Lines        7460     7373      -87     
==========================================
- Hits         6003     5902     -101     
- Misses       1126     1135       +9     
- Partials      331      336       +5

Impacted Files	Coverage Δ
transpiler/variables.go	80.9% <100%> (+0.17%)	⬆️
transpiler/call.go	68.15% <100%> (+0.31%)	⬆️
transpiler/enum.go	91.28% <100%> (+0.18%)	⬆️
util/goast.go	88.23% <100%> (-2.05%)	⬇️
transpiler/translation_unit.go	81.48% <100%> (+1.48%)	⬆️
transpiler/declarations.go	82.26% <69.23%> (-1.21%)	⬇️
transpiler/unary.go	74.32% <75%> (+0.1%)	⬆️
transpiler/binary.go	66.07% <85.71%> (+2.3%)	⬆️
transpiler/union.go	91.17% <90%> (-8.83%)	⬇️
... and 4 more

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[Konstantin8105]

For success of that PR need #525

[Konstantin8105]

Not ready for review

[elliotchance]

Reviewed 6 of 6 files at r1, 1 of 1 files at r2.
Review status: all files reviewed at latest revision, all discussions resolved, some commit checks broke.

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Comments from Reviewable

[Konstantin8105]

Ready for review, if by travis is Ok.

[Konstantin8105]

ready for review.

[elliotchance]

Reviewed 6 of 6 files at r3.
Review status: all files reviewed at latest revision, 1 unresolved discussion.

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transpiler/binary.go, line 297 at r3 (raw file):

			var findUnion func(ast.Node)
			var UnionNode ast.Node
			findUnion = func(node ast.Node) {

Please avoid anonymous functions.

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Comments from Reviewable

[Konstantin8105]

Review status: 8 of 10 files reviewed at latest revision, 1 unresolved discussion.

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transpiler/binary.go, line 297 at r3 (raw file):

Previously, elliotchance (Elliot Chance) wrote…

Please avoid anonymous functions.

Done

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Comments from Reviewable

[Konstantin8105]

Ready for review.

[elliotchance]

Reviewed 2 of 2 files at r4, 6 of 6 files at r5.
Review status: all files reviewed at latest revision, all discussions resolved.

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Comments from Reviewable