Adding support for time zones

As previously mentioned, by default, Julia's date/time objects operate in local time, completely ignoring time zones. However, we can easily extend them to become time-zone aware using the TimeZones package. Please install it in the usual way:

julia> using Pkg
pkg> add TimeZones

Once we inform the compiler that we'll be using TimeZones, a wealth of timezone-related functionalities become available at our fingertips.

We can start by exploring the available time zones:

julia> timezone_names() 
439-element Array{AbstractString,1}: 
 "Africa/Abidjan" 
 "Africa/Accra" 
# output truncated

Let's create a time zone object for Amsterdam:

julia> amstz = TimeZone("Europe/Amsterdam") 
Europe/Amsterdam (UTC+1/UTC+2)

In Julia, a TimeZone is an abstract type that represents information regarding a specific time zone, which means that it can't be instantiated—we can't create objects of this type. Instead, one of its two subtypes will be automatically used—VariableTimeZone...