Perform multiple Text To Image operations when multiple lines of text are entered

[cah-thomas-halter]

The input box already takes multiple lines of input, but anything entered after a carriage return is currently ignored. It would be nice if the UI could iterate over each line in the input and perform the Text To Image operation using the current settings.

This would allow me to batch process multiple Text To Image operations, rather than having to execute them one at a time.

[Leland]

Also see #96