RchivalTag versions

upcoming:
	- add argument "show_time_limits" in plot_TS/DepthTS

RchivalTag_0.1.2 -- June 17, 2020 (Robert Bauer)
        - added dygraph version of plot_DepthTS

RchivalTag_0.1.1 -- February 7, 2020 (Robert Bauer)
        - added min_perc argument in hist_tad, hist_tat and ts2histos-function to define a minimum data coverage for histogram entries obtained through time series data.
        - added new function read_TS to read in time series data
        - added new functions plotDepthTempTS, plotDepthTempTS_resampled, plotDepthTempTS_resampled_PDT to plot depth-temperature time series data with colorized temperature values (or alternative y and z-variables)
        - added new function resample_PDT and resample_TS to resample temperature time series data or PDT data (e.g. to facilitate plotDepthTempTS plots)

RchivalTag_0.1.0 -- October 30, 2019 (Robert Bauer)
        - fixed daytime rendering problem in classify_DayTime, plot_TS and plot_DepthTS

RchivalTag_0.0.9 -- September 16, 2018 (Robert Bauer)
        - added cex.main, cex.lab, cex.axis, cex.axis2 arguments to plot_TS, plot_DepthTS and empty.plot_TS functions
        - fixed daytime rendering problem in plot_TS and plot_DepthTS

RchivalTag_0.0.8 -- June 18, 2018 (Robert Bauer)
        - added date_format and tz arguments to the read_histos- and read_PDT-functions.
        - function get_geopos is added

RchivalTag_0.0.7 -- January 29, 2018 (Robert Bauer)
        - interp-function from the akima package replaced in internal calls by the approx function of the stats-package
	- added function resample_TS

RchivalTag_0.0.6 -- June 9, 2017 (Robert Bauer)
	- small bug fixed in read_histos

RchivalTag_0.0.5 -- June 8, 2017 (Robert Bauer)
	- adding average and standard deviation estimation for depth and temperature values insisde the read_histos and ts2histos functions

RchivalTag_0.0.4 -- April 25, 2017 (Robert Bauer)
	- improving performance (speed) of plot_TS/plot_DepthTS

RchivalTag_0.0.3 -- April 10, 2017 (Robert Bauer)
	- small bugs fixed in plot_TS/plot_DepthTS and read_PDT

RchivalTag_0.0.2 -- March 22, 2017 (Robert Bauer)
	- small bug in hist_tad/hist_tat functions fixed
        - adding example on back-to-back histogram for day vs night TaD-data (see: ?hist_tad)