GEODE-4112: Replaced FunctionAdapter with Function

[nabarunnag]

* This commit is specific to geode-lucene only
* Before making any changes serialVersionUID was generated for the files which were to be modified.
* The FunctionAdapters were replaced with Function

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[jhuynh1]

Looks good to me. We might want to add a note to show that java serialization isn't really used for these functions but that the serialVersionUID was added anyways.