Better functionality for working with pattern lists

[jkboyce]

Creating or editing a pattern list currently cannot be done within the application, but must be done in a text editor.

The idea here is to add functionality to allow one to create and edit pattern lists entirely within the application. Needed features consist of:

• create a new pattern list
• duplicate a pattern list
• change the title
• drag patterns within a list to reorder them
• add one of the currently-animated patterns (for simplicity could add it at the end)
• drag patterns between lists to copy them
• add a non-pattern line (e.g., for headings)
• delete a line
• edit displayed text for a line

[jkboyce]

these features were implemented and committed to the master branch