Made get_command() method respect multiple parents, added shell of set_instance_value(), drastic changes to FlowInstanceValue class
first version with STDOUT and STDERR definitions
removed redundant get_param() def
Made Flow.get_command() a recursive search
Added exec_dir attribute to Command class
Added EMERGENCE_EXAMPLE_DATA_ROOT to settings.common
Task runner now sets cwd = Task.exec_dir
Fixed indent levels, upload now uses settings file
Added -p (prefix) option to better control output
Moved exec_dir attribute from Command to Step class, added FlowInstanceValue class
Removed Flow.get_data_path() in favor of Flow.exec_dir
Fixed spelling error in variable name 'commmand', made CommandParam.prefix attribute nullable