Release 0.1.2

• Add /xmr chart command that responds with a chart of Monero's price, with 30s cooldown (API quotas)
• Chane the bot's nick every 30s, rotating between Monero price in USD, EUR, BTC, and "Monero Chad"
• Display 24h change in /xmr price
• Use embeds for relaying Monero Observer news
• Use embeds for all command responses
• Fix typo in description of /time
• Custom launch banner
• Lower TTL of price info cache to 1 minute