Add several tests in search

Added tests
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* Future deleteAsync(java.lang.Iterable)
* Future deleteAsync(java.lang.String[])
* GetResponse getRange(com.google.appengine.api.search.GetRequest$Builder)
* Future getRangeAsync(com.google.appengine.api.search.GetRequest$Builder)
* Future getRangeAsync(com.google.appengine.api.search.GetRequest)
* Future putAsync(java.lang.Iterable)
* Future putAsync(com.google.appengine.api.search.Document$Builder[])
* Future searchAsync(com.google.appengine.api.search.Query)
* Future searchAsync(java.lang.String)
* Future getIndexesAsync(com.google.appengine.api.search.GetIndexesRequest$Builder)
* Future getIndexesAsync(com.google.appengine.api.search.GetIndexesRequest)
* SearchService getSearchService(com.google.appengine.api.search.SearchServiceConfig)