addind options "expression","expoperand" and "optype" to <cell> in <repeatingrow>
addind <repeatingrow> in <cell>
remake defaultnullvalue in <repeatingrow> inside <cell>
defaultnullvalue if none of needed json data
adding property calculation with data from json
adding property calculation with data from json
adding property extraction from data from json
adding util classes
Merge pull request #21 from novikam/master

Extending function set