#' @param input character or raw, containing the url for the retrieval or a path to the data file, or raw XML.
#' @param asDateTime logical, if \code{TRUE} returns date and time as POSIXct, if \code{FALSE}, character
#' @param tz character to set timezone attribute of datetime. Default is UTC (properly accounting for daylight savings times based on the data's provided time zone offset).
#' Possible values include "America/New_York","America/Chicago", "America/Denver","America/Los_Angeles",
#' "America/Anchorage","America/Honolulu","America/Jamaica","America/Managua","America/Phoenix", and "America/Metlakatla"
#' @param tz character to set timezone attribute of dateTime. Default is "UTC", and converts the
#' date times to UTC, properly accounting for daylight savings times based on the data's provided time zone offset.
#' Possible values to provide are "America/New_York","America/Chicago", "America/Denver","America/Los_Angeles",
#' "America/Anchorage", as well as the following which do not use daylight savings time: "America/Honolulu",
#' "America/Jamaica","America/Managua","America/Phoenix", and "America/Metlakatla". See also \code{OlsonNames()}
#' for more information on time zones.
#' @return mergedDF a data frame source, time, value, uom, uomTitle, comment, gmlID
\item{asDateTime}{logical, if \code{TRUE} returns date and time as POSIXct, if \code{FALSE}, character}
\item{tz}{character to set timezone attribute of datetime. Default is UTC (properly accounting for daylight savings times based on the data's provided time zone offset).
Possible values include "America/New_York","America/Chicago", "America/Denver","America/Los_Angeles",
"America/Anchorage","America/Honolulu","America/Jamaica","America/Managua","America/Phoenix", and "America/Metlakatla"}
\item{tz}{character to set timezone attribute of dateTime. Default is "UTC", and converts the
date times to UTC, properly accounting for daylight savings times based on the data's provided time zone offset.
Possible values to provide are "America/New_York","America/Chicago", "America/Denver","America/Los_Angeles",
"America/Anchorage", as well as the following which do not use daylight savings time: "America/Honolulu",
"America/Jamaica","America/Managua","America/Phoenix", and "America/Metlakatla". See also \code{OlsonNames()}
for more information on time zones.}
}
\value{
mergedDF a data frame source, time, value, uom, uomTitle, comment, gmlID