[C++] Split arrow::ChunkedArray into arrow/chunked_array.h

[asfimport]

There are plenty of scenarios where ChunkedArray is used separate from Table, it would probably make sense to split up the headers, implementation, and unit tests

Reporter: Wes McKinney / @wesm
Assignee: Wes McKinney / @wesm

Related issues:

• [C++] Clarify ChunkedArray chunking strategy and policy (is related to)

PRs and other links:

• GitHub Pull Request #7487

_{Note: This issue was originally created as ARROW-8800. Please see the migration documentation for further details.}

[asfimport]

Wes McKinney / @wesm:
Issue resolved by pull request 7487
#7487