Resolve "Overriding options in davinci script depends on order of special flag overwrite_data_options" & bug with bool passed via command line

Fixing two bugs related to setting boolean properties by command line:

• value passed via command line are always interpreted as string, so a conversion is applied when the properties are set
• 'overwrite_data_options' properties has to be set before any other one in order to know if the data options properties can be overriden in the job.

In addition the name of the 'overwrite_data_options' property has changed into 'override_data_options'

Closes #22 (closed)