read.ctd.sbe() rename arg should accept a character value

[dankelley]

I want it to be such that a user can do either

A <- read.ctd.sbe(..., rename = FALSE) |> rename("sbe")
B <- read.ctd.sbe(..., rename = "sbe")

to get identical results.

At present, an error is reported if a non-logical value is used for rename, so the change I have in mind will not require users to change their code. It will just be a simpler, one-step, method.

I actually thought we had this ... the reason I want to add it now is that I just wrote code assuming it worked ... that's a good test of things we ought to provide, I reckon.