ARROW-5110: [Go] implement reading struct arrays from Arrow file

[sbinet]

No description provided.

[sbinet]

needs #4157

[codecov-io]

Codecov Report

Merging #4158 into master will decrease coverage by 26.75%.
The diff coverage is 4.61%.

@@             Coverage Diff             @@
##           master    #4158       +/-   ##
===========================================
- Coverage   87.89%   61.13%   -26.76%     
===========================================
  Files         758       67      -691     
  Lines       92163     4912    -87251     
  Branches     1251        0     -1251     
===========================================
- Hits        81006     3003    -78003     
+ Misses      11040     1798     -9242     
+ Partials      117      111        -6

Impacted Files	Coverage Δ
go/arrow/ipc/file_reader.go	0% <0%> (ø)	⬆️
go/arrow/ipc/metadata.go	0% <0%> (ø)	⬆️
go/arrow/array/list.go	74.56% <0%> (-12.18%)	⬇️
go/arrow/array/struct.go	84.31% <100%> (+11.67%)	⬆️
python/pyarrow/ipc.pxi
cpp/src/arrow/csv/chunker-test.cc
cpp/src/parquet/column_page.h
cpp/src/parquet/bloom_filter-test.cc
cpp/src/arrow/array/builder_decimal.cc
cpp/src/plasma/client.cc
... and 687 more

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[sbinet]

PTAL @stuartcarnie @alexandreyc @nickpoorman

[stuartcarnie]

LGTM 👍