Merge pull request #3721 from sleuthkit/3503_kwsrch_refactor

...rg/sleuthkit/autopsy/keywordsearch/AdHocQueryRequest.java

...uthkit/autopsy/keywordsearch/AdHocSearchChildFactory.java

...sleuthkit/autopsy/keywordsearch/AdHocSearchDelegator.java

...leuthkit/autopsy/keywordsearch/AdHocSearchFilterNode.java

...org/sleuthkit/autopsy/keywordsearch/AdHocSearchPanel.java

...uthkit/autopsy/keywordsearch/DropdownListSearchPanel.java

.../autopsy/keywordsearch/DropdownSingleTermSearchPanel.java

...euthkit/autopsy/keywordsearch/ExtractedContentViewer.java

...g/sleuthkit/autopsy/keywordsearch/IngestSearchRunner.java

...hkit/autopsy/keywordsearch/KeywordSearchIngestModule.java

...rg/sleuthkit/autopsy/keywordsearch/SolrSearchService.java