Remove VoiceRegion enum and Guild.region attribute

This has been marked deprecated by Discord and it was more or less
usually out of date due to the pace they added them anyway.

discord/enums.py

@@ -30,7 +30,6 @@ __all__ = (
     'Enum',
     'ChannelType',
     'MessageType',
-    'VoiceRegion',
     'SpeakingState',
     'VerificationLevel',
     'ContentFilter',
@@ -220,35 +219,6 @@ class MessageType(Enum):
     guild_invite_reminder = 22
 
 
-class VoiceRegion(Enum):
-    us_west = 'us-west'
-    us_east = 'us-east'
-    us_south = 'us-south'
-    us_central = 'us-central'
-    eu_west = 'eu-west'
-    eu_central = 'eu-central'
-    singapore = 'singapore'
-    london = 'london'
-    sydney = 'sydney'
-    amsterdam = 'amsterdam'
-    frankfurt = 'frankfurt'
-    brazil = 'brazil'
-    hongkong = 'hongkong'
-    russia = 'russia'
-    japan = 'japan'
-    southafrica = 'southafrica'
-    south_korea = 'south-korea'
-    india = 'india'
-    europe = 'europe'
-    dubai = 'dubai'
-    vip_us_east = 'vip-us-east'
-    vip_us_west = 'vip-us-west'
-    vip_amsterdam = 'vip-amsterdam'
-
-    def __str__(self):
-        return self.value
-
-
 class SpeakingState(Enum):
     none = 0
     voice = 1