Added clousure support in parameters_field_mapping option values. Fixed typos in doc.
Merge pull request #22 from norzechowicz/action

Added clousure support in parameters_field_mapping option values. Fixed typos in doc.
Updated tree column type
Added hasColumnType method to DataGridInterface, fixed tests for GedmoTree
Merge pull request #23 from norzechowicz/tree

Updated tree column type and added hasColumnType to DataGridInterface.
Added getSource method for DataGridRowView.
Merge pull request #24 from beregond/rowview

Added getSource method for DataGridRowView.