ARROW-6284: [C++] Allow references in std::tuple when converting tuple to arrow array

[ozars]

Currently std::vector<std::tuple> can be converted to a table by treating each tuple as a row and by building arrays corresponding to each element of the tuple. This PR allows reference types (and const reference types) in elements of std::tuple which is to be converted. This is useful for converting user defined types. For example a vector of CustomType:

struct CustomType {
  int8_t i8;
  uint64_t u64;
  bool b;
  std::string s;

  auto tie() const {
    return std::tie(i8, u64, b, s);
  }
};

can be converted to a table like this:

using boost::adaptors::transform;

std::vector<CustomType> rows();
std::shared_ptr<Table> table;
auto rng_rows =
  transform(rows(), [](const CustomType& c) { return c.tie(); });
TableFromTupleRange(default_memory_pool(), rng_rows, names, &table);

This makes it easier to convert user defined types to arrow tables.

[codecov-io]

Codecov Report

Merging #5112 into master will increase coverage by 1.58%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #5112      +/-   ##
==========================================
+ Coverage   87.64%   89.22%   +1.58%     
==========================================
  Files        1014      731     -283     
  Lines      145922   104999   -40923     
  Branches     1437        0    -1437     
==========================================
- Hits       127887    93690   -34197     
+ Misses      17673    11309    -6364     
+ Partials      362        0     -362

Impacted Files	Coverage Δ
cpp/src/arrow/stl.h	100% <ø> (ø)	⬆️
cpp/src/arrow/stl-test.cc	100% <100%> (ø)	⬆️
cpp/src/arrow/util/thread-pool-test.cc	97.66% <0%> (-0.94%)	⬇️
python/pyarrow/tests/test_parquet.py	96.38% <0%> (-0.07%)	⬇️
js/src/util/fn.ts
go/arrow/memory/memory_avx2_amd64.go
rust/datafusion/src/execution/filter.rs
rust/arrow/src/csv/writer.rs
rust/datafusion/src/bin/main.rs
go/arrow/ipc/file_reader.go
... and 277 more

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[fsaintjacques]

LGTM!