add Support for MainTopic in the PartnerWizard

[jr-dig-orgel]

as @mgrani reported in EEXCESS/recommender#30 we need Support for the MainTopic in the PartnerWizard

[mgrani]

it is not only about the main topic, but the queries Rahmen Beruf did not yield any results without a main topic.

[jr-dig-orgel]

okay, also this should be solved by changeing the QueryGeneration Strategy.
In the PartnerWizard (first step) we have only a very simple QueryGeneration. The goal of this step is getting first results for creating a mapping and build a first version of the PartnerRecommender. The second step is for refinement. Am I right?