Epoch timestamp to Datetime converter

Problem Statement The calculator provides plenty of tools to help developers: a Programmer mode, conversion from a base to another, a binary number editor, Data converter, ... but one tool is missing to complete the ideal toolbox: a converter to convert "human" date/time to system time (and vice-versa).

Evidence or User Insights While it's easy to convert kilobytes to gigabytes, it's not easy to convert Epoch time or FILETIME struct to "human" time without using a tool. Such a tool, even if basic, doesn't exist in Visual Studio or in Visual Studio Code, and only a few developers will install an app only for this purpose, so we mainly rely on web to verify system times when we debug an application.

A simple chrome extension converting dates to epoch time (only) has more than 16K downloads for example.

Proposal We should add an extra option in Date Calculation, allowing developers to not only convert dates from/to epoch time, but also from/to FILETIME, Mac time, LDAP time, Chromium time, etc...

Goals

• Users can convert a "human" date to a system time.
• Users can convert a system time to "human" date.
• Users can easily copy the system time to the Programmer calculator

Non-Goals

• Users can't directly convert a system time to another, but they can select a system time format in the combobox, type a system time, then select another system time format in the combobox, the Calculator will then display the same date/time in the new format.

Low-Fidelity Concept

(we will need to customize the timePicker to manage seconds/milliseconds or use another way to select a time)

We can also:

• display the date selected using the ISO-8601 format at the bottom of the window in local and UTC.
• add Datetime.Tick (https://docs.microsoft.com/en-us/dotnet/api/system.datetime.ticks?view=netframework-4.7.2)