How to upgrade weapons and armor in XCOM 2?

@garrison.jerde 

In XCOM 2, you can upgrade weapons and armor for your soldiers in the following ways:

1. Research new technologies: As you progress through the game, you'll unlock new technologies that will allow you to build better weapons and armor. Be sure to prioritize researching these technologies so that you can stay ahead of the enemy.
2. Build new facilities: Building facilities like the Proving Grounds will allow you to research and build experimental weapons and armor. These facilities can also allow you to build special ammo and grenades that can provide additional benefits to your soldiers.
3. Use the engineering bay: The engineering bay is where you can upgrade your weapons and armor. You can upgrade individual weapons and armor pieces or upgrade them all at once for a fee. Upgrades can include increased damage, better accuracy, and increased armor.
4. Use the black market: The black market is a place where you can buy and sell items, including weapons and armor. Sometimes, you'll find weapons and armor that have already been upgraded, which can save you time and resources.

Remember, upgrading weapons and armor is essential to keeping your soldiers alive on the battlefield. Be sure to prioritize this aspect of the game to ensure that you can stay ahead of the enemy.