asyncio: increase default concurrent request (meraki#159)

Pushes asyncio's maximum concurrent requests from 3 to 8. Please note additional concurrency rate limit information here: https://developer.cisco.com/meraki/api-v1/#!rate-limit

Author: coreGreenberet

meraki/config.py

@@ -52,7 +52,7 @@
 SIMULATE_API_CALLS = False
 
 # Number of concurrent API requests for asynchronous class
-AIO_MAXIMUM_CONCURRENT_REQUESTS = 3
+AIO_MAXIMUM_CONCURRENT_REQUESTS = 8
 
 # Optional partner identifier for API usage tracking; can also be set as an environment variable BE_GEO_ID
 BE_GEO_ID = ''