Rename `getImageList` to `getMIGX` or similar

[gadamiak]

At first, I need to say thank you for this incredibly useful extension! Now, I suggest renaming the getImageList snippet to getMIGX or similar but linking with MIGX itself. The current name is misleading -- my first thought was it's a fork of getResources.

[Bruno17]

The Name getImageList comes from my original custom-TV-input-type 'imageListTv' . I thought about that to rename it. But I'm not sure, because renaming will probably break allready running installations.

[anselmh]

Think this should be postponed to a major release (2.0) when many things have changed that might be incompatible, too.

[gadamiak]

That's a big change. Postponing it to a major release may be a good choice. Another name that came to my mind is getJSON as its quite generic snippet.