Add multiline text to array functionality (Make large text blobs more readable)

[lowell80]

Add ability to replace text strings containing newlines (aka \n) with an array of individual lines.

This could be added to jmespath as a simple split() function to complement the existing join() command. But I think the most helpful bits would be in the jsonformat command. This would make multiline text blobs much more readable, the purpose is less about programmatic manipulation.