Tries to convert character into a Date object. If this fails, the program will be stopped and an error message shown to the user
convert_to_date_with_trycatch(input, input_name)
Will return input as a Date is it can be converted into one. Else will stop the program and issue the user with an error message.
A character of length 1, to convert into a Date object.
A character string that reflects the name of the input (to inform the user).