Moved BudgetTemplateNode's unique_together validation to BudgetTemplateNodeRelation;
Added path field to BudgetTemplateNode with creation hook in save;
Added PATH_SEPARATOR
Initial Implementation of BudgetParser;
Changed implementation of _clean_object to a more generic one using the new ITEM_ATTRIBUTES attribute;
Initial implementation of templates inheritance for importing IL's municipal budgets;
Renamed _save_object to _save_item;
Changed _save_item's implementation to also accept saved nodes in BudgetTemplateParser;
Implemented _set_path;
Moved _lookup_node to BudgetTemplateParser
Fixed date formatting in parseDate
Added scrolling and max-height to import_errors