Domain values for value generators from external source

[nivancevic]

Implement a data value loader that can be used to define value generator domain values in an external source - a file.

For example:

value: random(domain('<path to resource>'), normal(0.4, 0.01))

defines a random value generator where the domain values are loaded from a external file.

[vajda]

I'd call it fromFile('path') or file('path') domain is a bit strange name IMHO.
Or even better, call it textFile, maybe have also csvFile('path', columnSeparator, recordSeparator) and also excelFile('path')