Only set variables if transformation returns values =! None
Fail early by not catching mapper and site import exceptions
Variables are either set or != None => remove None case from mandatory vars check
Sort variables on output
Append newline at output end
Rename ncifIPAddress => ncifIPAddresses
Make SLP_SCOPE_LIST a single value
Sort by prio in all default projections
Fix default value handling in single_value_local_over_global
Fix previous_variable_value
Add plain_value projection