Merge kfm into rushd

[kaseylove]

No description provided.

[meson800]

The current KFM file layout is:

wells:
  - condition_name: A2-A5

Let's change it to use the rushd format, and also possibly let you pick metadata columns/combos of columns.

Something like:

metadata:
  condition:
     - condition_name: A2-A5

[kaseylove]

• Allow multiple images per well, z stacks
• Allow rushd to map images to wells that have been previously kfm'd using unmoved
• Specify which metadata columns to use in new filename
• Keep access to kfm on command line
• Write tests @maryehmann