Add a new function for getting ems data formated

The current `rems_to_aquachem()` was meant as a one-stop method for converting EMS data to a format good for AquaChem, but now, this data is used for other purposes, and the AquaChem format is a bit difficult to work with.

Consider adding another function together and format the data without units in a format easier to work with in R (without having to use `units_remove()`.

Start by reading the existing rems_to_aquachem() function and the units_remove() workflow. Add a separate conversion function that returns EMS data without units in a format easier to use in R, and verify that its output meets that goal.

Written by the indexing model from the issue text.