optimizing lightpush send time using optimistic stream creation

[danisharora099]

This is a feature request

Problem

reference to #1465 (comment), we currently create streams with remote peers for a protocol lazily. ie, when lightpush.send() is called, a stream is created then - thus adding to the time delays for the send() function.

Proposed Solutions

• optimistically open streams with peers
  • instead of opening a stream during the sending of message, open one beforehand
  • create a small pool of streams
  • refill the pool as soon as we use up a stream

Notes

Once the above is done, look into work for reducing time taken by pipe()

[danisharora099]

Done with #1516