message: constants should be defined with const
diff: @@ -3,7 +3,7 @@ pub use self::association::{UdpAssociationManager, UdpInboundWrite};
  pub mod association;
  /// Packet size for all UDP associations' send queue
  -pub static UDP_ASSOCIATION_SEND_CHANNEL_SIZE: usize = 8192;
  +pub const UDP_ASSOCIATION_SEND_CHANNEL_SIZE: usize = 4096;
  /// Keep-alive channel size for UDP associations' manager
  -pub static UDP_ASSOCIATION_KEEP_ALIVE_CHANNEL_SIZE: usize = 256;
  +pub const UDP_ASSOCIATION_KEEP_ALIVE_CHANNEL_SIZE: usize = 256;
  