2017.2: update release notes
2017.2: update release notes

lokik/sfepy,BubuLK/sfepy,rc/sfepy,BubuLK/sfepy,lokik/sfepy,vlukes/sfepy,lokik/sfepy,lokik/sfepy,sfepy/sfepy,rc/sfepy,sfepy/sfepy,sfepy/sfepy,vlukes/sfepy,rc/sfepy,vlukes/sfepy,BubuLK/sfepy