Implement fix for future rate limiting change in discord.
Implement fix for future rate limiting change in discord.

rapptz/discord.py,Harmon758/discord.py,imayhaveborkedit/discord.py,variablehair/Eggplantato,khazhyk/discord.py,Theoretical/UselessBot,jhgg/discord.py,Harmon758/discord.py,Rapptz/discord.py,lgkern/PriestPy,mgardne8/discord.py