Unified timeout for sending a message

[rahulghangas]

Currently the Send method in the peer module, and consequently, the Send method in transport uses a user supplied context for timeout. This causes multiple timing issues across gossipping and syncing if not configured with proper times. Also, using two different timeouts can get confusing. There are two potential solution that come to mind

1. remove the context parameter and have a single timeout for Send that gets configured while creating the transport layer.
2. Since some messages might be quite big and might not finish in the timeout specified in the transport layer, create two methods for sending a message
   • where the timeout field from the transport layer is used
   • where the user supplies the context with a custom timeout

[rahulghangas]

This came up while working on a fix for #70