update importNCRNwater: include sample depth/units into the water data obj

[aaronweed]

Since NETN (and others) collect data across depths a sample depth data field needs to be added into the data object created by the importNCRNwater function. NETN can create its own function to do so or args to select on line 51 can be updated to pass the correct fields from imported data.

E.g., lines 50-51 from importNCRNwater following pmap():

dplyr::filter(Indata, SiteCode == !!SiteCode, Characteristic == DataName) %>% dplyr::select(Date, Value, TextValue, MQL, UQL, Censored, ValueCen)})

to

dplyr::filter(Indata, SiteCode == !!SiteCode, Characteristic == DataName) %>% dplyr::select(-cols we don't want)}