switch to using Sequence<VariantValue> instead of vector<VariantValue> - since the former triggered bugs iwth visual studio.net and clang++3.4 (where not writing regtests to test those libs unless needed) and stroika seems to handle std::initailizer_list correctly
lose recently added vector<VariantValue> ({ 19 }); test - fails on clang++3.4 and visual studio.net 2k13 - but not important for us to test those libs