[Java] Implement ApproxEqualsVisitor comparing approx for floating point

[asfimport]

Currently we already implemented RangeEqualsVisitor/VectorEqualsVisitor for comparing range/vector.

And ARROW-6211 is created to make ValueVector work with generic visitor.

We should also implement ApproxEqualsVisitor to compare floating point just like cpp does

https://github.com/apache/arrow/blob/master/cpp/src/arrow/compare.cc

Reporter: Ji Liu / @tianchen92
Assignee: Ji Liu / @tianchen92

Related issues:

• [Java] Remove dependency on RangeEqualsVisitor from ValueVector interface (is blocked by)

PRs and other links:

• GitHub Pull Request #5118

_{Note: This issue was originally created as ARROW-6250. Please see the migration documentation for further details.}

[asfimport]

Ji Liu / @tianchen92:
cc @pravindra

[asfimport]

Pindikura Ravindra / @pravindra:
Issue resolved by pull request 5118
#5118