Implement changes to author relevancy in keyword searches on blackcat-test

[lovinscari]

As a follow up to ticket #1114 please implement the suggested changes to boost author field in keyword search by "reduce that difference, say set title_precise_tesim^100 and author_tesim^75, author searches through keyword search will prioritize results that match the author. In general, although boosting some fields is helpful, we need to avoid boosting them by such a large factor that they reduce the relevancy of all other fields completely." We will keep the test to blackcat-test for now as we perform additional tests.

[abelemlih]

@lovinscari Regarding this ticket, if we add any changes to blackcat-test, we will need to make a code change that will eventually need to be released to production. We currently do not make any changes directly to an instance, like Test or Arch, without having it be committed. Therefore, we may need to wait and decide how exactly we want to move forward with changing boost factors, then make a change that gets deployed to all instances including production.