[Java] Allow for expanding underlying buffer size after allocation

[asfimport]

There are currently some reAlloc methods, but not exposed at the vector level. Would be useful to expose them to allow for growing vector capacity without losing current data.

Reporter: Emilio Lahr-Vivaz / @elahrvivaz
Assignee: Emilio Lahr-Vivaz / @elahrvivaz

Related issues:

• Arrow 0.3 release (blocks)

_{Note: This issue was originally created as ARROW-815. Please see the migration documentation for further details.}

[asfimport]

Wes McKinney / @wesm:
Issue resolved by pull request 534
#534