Allow replaceable ad-hoc data for test input

[coinzdude]

Consider a JSON document support for ad-hoc data to use in a test execution. Allow a test set of data (or more than one?) to be defined within the project config, and allow the test set data to be persisted with the SIDE file save.

Proposed test set data is a simple JSON document with name/value pairs in an object, so values below would replace matched "Store" entries:

store, Username, scriptUser

{
"Username":"someuserID",
"Password":"!@#$",
"SelectListVal":"SelectThisItem"
}