COEUS-107 Changed QuestionnaireAnswerServiceImpl.java to prevent NullPointerException when dereferencing the getQuestionnaireQuestion() result.

Amends:
	Author: Lance Speelmon
	Description: errors on trying to open questions tab or proposal summary tab in proposals
	https://github.com/rSmart/kuali_kc/commit/d607b2d5923611cf2d1585cb01d8c26239497e9c