[docs] Adding Initial Documentation (#3139)

## Overview
Adding Markdown, simplified versions of the docs hosted on [External Site](https://evilperson1337.notion.site/Eden-Guides-2b057c2edaf680149310edee3024565d).

### Guides Added

- Adding Games into Steam with Steam ROM Manager and Eden
- Adding Eden as an emulator into Steam ROM Manager
- How to modify the Date/Time in Eden
- How to configure controller profiles
- How to set controller profiles per game
- Eden fails to launch but does not leave a log (Windows)
- How to configure motion/gyro controls on steam deck
- How to access logs
- How to import saves into Eden (windows)
- How to install Atmosphere mods
- How to install Updates/DLC
- Quick Start Guide (Steam Deck)
- Quick Start Guide (Windows)
- Allowing Eden to Run on MacOS (MacOS)
- Sync Game Saves with Syncthing (General)
- Sync Game Saves with Syncthing (Windows)
- Sync Game Saves with Syncthing (Linux)
- Using Amiibo with Eden (Windows)
- Using Cheats with Eden (Windows)
- Using Cheats with Eden (Android)

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/3139
Reviewed-by: Lizzie <lizzie@eden-emu.dev>
Reviewed-by: MaranBr <maranbr@eden-emu.dev>
Co-authored-by: Evilperson1337 <Evilperson1337@proton.me>
Co-committed-by: Evilperson1337 <Evilperson1337@proton.me>

docs/user/AlterDate-Time.md

@@ -0,0 +1,20 @@
+# Setting a Custom Date/Time in Eden
+
+Use this guide whenever you want to modify the Date or Time that Eden reports to games.  This can be useful for modifying RNG elements, skipping wait times in games, etc.
+
+**Click [Here](https://evilperson1337.notion.site/Setting-a-Custom-Date-Time-in-Eden-2b357c2edaf680acb8d4e63ccc126564) for a version of this guide with images & visual elements.**
+
+---
+
+### Pre-Requisites
+
+- Eden set up and fully configured
+
+---
+
+## Steps
+
+1. Navigate to *Emulation → Configure*.    
+2. Click on the **System** item on the left-hand side navigation, then check the *Custom RTC Date* box.
+3. The Date/Time option now becomes editable.  Set it to the value you want and hit **OK**.
+4. GREAT SCOTT! We have time traveled!  You can of course go forward or backward in time (as long as it is not before the year 1970) and your game should update accordingly (e.g. certain *Super Mario Odyssey* moons that take time for flowers to grow will now be fully grown.).