%notin%                 notin helper function. Opposite of 'in'
                        function.
assign_to_R_env         Add variable to R environment (in contrast to
                        system environment).
check_if_unique_rows    Takes a data.table dataset and checks if for
                        each unique element in a specified column there
                        is exaclty one row.
clean_path_name         Clean paths to surely have a tailing slash or
                        not.
cleanup_old_logfile     Archives the current logfile and creates a new
                        blank one.
clear                   Clean the console and environment-variables.
close_all_connections   Unset/close all open connections.
dt_row_to_string        Get the content of a data.table row in
                        print-ready format.
equals2                 Robust compare two elements and return true if
                        both elements are the same. False otherwise. No
                        'NA' or 'NULL'.
feedback                Function to feedback messages either to the
                        user and/or to the console and to the logfile.
feedback_get_formatted_string
                        Format the feedback string
feedback_to_console     Print to the console. Internal use only.
feedback_to_logfile     Add to the logfile. Internal use.
feedback_to_logjs       Feedback to the gui/browser-console with logjs.
                        Internal use.
feedback_to_ui          Feedback to the user with a modal. Internal
                        use.
file_lines_to_list      Read in lines from a file and store it in a
                        list.
firstup                 Converts the first letter of the input string
                        to uppercase.
format_posixct          Formats a given POSIXct timestamp without the
                        need of manually specifing format parameters.
get_config              Reads a config yaml file and return the value
                        for a given key.
get_current_timestamp   Quickly get the current time stamp without the
                        need to handle format-options etc.
is.empty                Check for empty/'NA'/'NULL'/'NaN'/etc. values.
is_date_format          Checks if a string matches a given date format.
log_get_current_options
                        Get the current settings for the logging
                        function as list.
log_get_default_options
                        Get the default settings for the logging
                        function as list.
log_internal_test       Internal function for debugging only.
log_map_type_to_loggertype
                        Get the logger type from the type string (the
                        argument of the 'feedback()' function)
log_remove_options      Remove all log-related options from
                        'options()'.
log_set_defaults        Set default options for all log-functions
number_to_position      Converts an integer number to its "verbal
                        position".  1 -> "1st", 2 -> "2nd", 3 -> "3rd",
                        4 -> "4th", ...
paste2                  Normal 'paste' function with additional
                        'collapse_last' argument.
paste_pct_sum           Get the percentage of two values pretty
                        formatted.
pretty_timestamp        Quickly get a pretty timestamp without need to
                        handle format-options etc.
rep2                    Repeat something with the ability to also
                        collapse the output.
robust_round            Round numbers without problems.
setdiff_all             Get the difference of two vectors in both
                        directions.
setenv2                 Assign variables to the system environment.
setenv_file             Set all variables of a '.env' file to the
                        system environment.
string_replacements     Clean string with a given set of replacements.
time_diff_print         Calculate time difference of two timestamps,
                        round the value and return a string with
                        suiting unit.
trim.space              Trim Spaces of a string.
vgsub                   Vectorised string replacement.
