Add option to save and export configuration file

[AmyMikhail]

Problem statement:

The first time users use the app, they will need to provide:

• acceptable control ranges (which change with each kit batch)
• ranges for interpreting results (which are specific to the kit being used but do not change with each batch)

If users are performing a run with only some of the well strips from a particular kit batch, they would need to enter the same parameters each time they ran more well strips from the same batch, which is a bit labour intensive.

Likewise, entering the results interpretation ranges rather than hard-coding them into the app allows the app to be used with different kits, but does make parameter entry a bit labour intensive for users who are using the same kits most of the time.

Proposed solution:

Include all required parameters as separate input variables, but add an actionButton to save the parameters in an editable configuration file (.csv). The option to upload this configuration file during subsequent uses of the app would also need to be added.