Web emulator support

[ovosimpatico]

This PR adds support for online emulation of some games from Myrient, using EmulatorJS

This feature can be disabled by setting EMULATOR_ENABLED=false in the .env or in docker-compose.yml, disabling entirely the emulator page, all routes related to it and its info on the about page.

Visual changes:

The results page now has a "Play" button on supported platforms:

This is the new emulator webpage, running a game:

Information about the web emulator has been added to the about page:

Naive filename checking for non-game files is implemented, and triggers a warning box being shown to the user (this will not block the emulator, it's only meant as a warning):

Supported platforms:

Nintendo Systems

• Nintendo 64
• Nintendo DS
• Nintendo Entertainment System
• Nintendo Game Boy
• Nintendo Game Boy Advance
• Nintendo Game Boy Color
• Super Nintendo Entertainment System

Atari Systems

• Atari 2600
• Atari 5200
• Atari 7800
• Atari Jaguar
• Atari Lynx

Sega Systems

• Sega 32X
• Sega CD *
• Sega Game Gear
• Sega Master System
• Sega Mega Drive
• Sega Saturn

Commodore Systems *

• Commodore 64
• Commodore 128
• Commodore Amiga
• Commodore PET
• Commodore Plus-4
• Commodore VIC-20

Sony Systems

• Sony PlayStation 1

Other Systems *

• Arcade
• ColecoVision
• Panasonic 3DO

• disabled, needs fixing

[alexankitty]

Looks good to me, merging.