Update the output columns from fill_tics to include separation, magnitude difference, and weight

[christinahedges]

The fill_tics function can return the separation and magnitude difference as columns, but the function to create the target list must change those columns to ones ARK can accept. I've updated the fill_tics function and the _add_xmatch_column function to do that. I also made the xmatch column pipe delimited.

[tylerapritchard]

The functionality looks good to me and I like that we can have easier to parse feedback from fill_tics which is likely to get used internally, while maintaining the clear purpose of create_target_list, and that a few rough edges of the code were smoothed out.

Its passing tests and my quick once over on the functionality looked good.

main question - why the new target_list.csv? Was this a mistake, or is it intended to illustrate what a complete target list looks like and we should add a note to that effect in the readme somewhere? If that should this be in tutorials directory?

[tylerapritchard]

Was this intended?

[christinahedges]

@tylerapritchard thank you for the review! I think the extra target list was a mistake, I've just deleted it. I have uncommented the test and put that string back in the xmatch column. I think it's useful to have it in there, especially as you are prepending a warning.

If the tests pass and you like this you can merge and release it!