Source: Shutterstock It’s a volatile day for natural gas stocks and funds. Some of the most notable names include the United States Natural Gas Fund (NYSEARCA:UNG), ProShares Ultra Bloomberg Natural Gas (NYSEARCA:BOIL) and ProShares UltraShort Bloomberg Natural Gas (NYSEARCA:KOLD). The catalyst for today’s move is news from a European Union (EU) diplomat that the G7…