as of WWDC 2014 APNs is allowing max. 2048
adding category aps field and test
using latest of netty
Merge pull request #112 from matzew/Netty4023

using latest of netty
Merge pull request #108 from matzew/iOS8_cat

ios8 category field support
Merge pull request #105 from matzew/New_max_payload_size

as of WWDC 2014 APNs is allowing max. 2048