Add support for function pointers. Fixes #85 and #157

[Konstantin8105]

Not ready for review

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This change is 

[elliotchance]

I will wait until you say its ready for review 😄

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Review status: 0 of 14 files reviewed at latest revision, all discussions resolved, some commit checks failed.

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Comments from Reviewable

[codecov]

Codecov Report

Merging #469 into master will decrease coverage by 1.02%.
The diff coverage is 69.65%.

@@            Coverage Diff             @@
##           master     #469      +/-   ##
==========================================
- Coverage   80.97%   79.95%   -1.03%     
==========================================
  Files         145      145              
  Lines        6565     6719     +154     
==========================================
+ Hits         5316     5372      +56     
- Misses        980     1048      +68     
- Partials      269      299      +30

Impacted Files	Coverage Δ
ast/implicit_cast_expr.go	91.3% <ø> (ø)	⬆️
program/program.go	82.92% <100%> (+2.64%)	⬆️
transpiler/translation_unit.go	73.68% <100%> (+0.71%)	⬆️
ast/array_subscript_expr.go	90.47% <100%> (+1%)	⬆️
types/resolve.go	75.57% <100%> (+0.94%)	⬆️
types/sizeof.go	90.69% <100%> (+0.22%)	⬆️
transpiler/binary.go	61.14% <47.05%> (-2.93%)	⬇️
transpiler/variables.go	80.35% <50%> (-1.58%)	⬇️
transpiler/branch.go	75.12% <50%> (-0.78%)	⬇️
transpiler/declarations.go	82.67% <60%> (-1.47%)	⬇️
... and 12 more

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[Konstantin8105]

Not ready in according to travis

[Konstantin8105]

Removed list #85

[Konstantin8105]

Ready for review

[Konstantin8105]

If you want, then I can try to separate to small PRs.

[elliotchance]

This is a such a big and great feature it will be the v0.19.0 Uranium release 👍

[elliotchance]

Reviewed 11 of 16 files at r1, 6 of 7 files at r2, 3 of 4 files at r3, 1 of 1 files at r4.
Review status: all files reviewed at latest revision, all discussions resolved, some commit checks failed.

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Comments from Reviewable