FTB Placeholders

Adds placeholder items and icons for FTB quests, so your quests look better!

Item Placeholders:

• Exp 
• Talent, Passive, Ascendancy Point Icons [Mine and Slash]

Mob Placeholders:

• Minecraft Hostile Mobs
• AlexsMobs
• MowziesMobs
• TwilightForest
• Undergarden
• MonsterPlus
• Friends&Foes
• IllagerInvasion
• Born-In-Chaos

I will add more placeholders as i progress