Add ability to specify empty tip rack slots

[EvanKirshenbaum]

At the end of the run, some tip rack slots will be empty because they were used to transfer products and some will need to be emptied (or, with #170, will be emptied at the end of the run) because they were used to transfer reagents and are therefor dirty. Currently, the Opentrons code assumes that all tip rack slots needed are full, starting from A1, so before you can do another run, you need to refill these slots, either from another source or by moving tips from the end of the sequence.

It would be useful to be able to specify, either by the JSON config file or, more likely, by a command-line parameter, which slots should be seen as empty or otherwise unavailable.

Migrated from internal repository. Originally created by @EvanKirshenbaum on Jun 13, 2022 at 11:51 AM PDT.

[EvanKirshenbaum]

Here is an example program of tip tracking with refills. If I understand the program correctly, it uses a json file to get the initial tip log:

folder_path = '/data/your_path'
tip_file_path = folder_path + '/tip_log.json'

Migrated from internal repository. Originally created by Mark Huber on Aug 09, 2022 at 11:19 AM PDT.