fa5587fe71 qa: wait_for_verack by default (MarcoFalke)
Pull request description:
This removes the need to do so manually every time a connection is added.
Tree-SHA512: a46c92cb4df41e30778b42b9fd3dcbd8d2d82aa7503d1213cb1c1165034f648d8caee01c292e2d87d05b0f71696996eef5be8a753f35ab49e5f66b0e3bf29f21
This commit adds a boolean option `-enablebip61`, defaulting to `1`, that
can be used to disable the sending of BIP61 `reject` messages. This
functionality has been requested for various reasons:
- security (DoS): reject messages can reveal internal state that can be
used to target certain resources such as the mempool more easily.
- bandwidth: a typical node sends lots of reject messages; this counts
against upstream bandwidth. Also the reject messages tend to be larger
than the message that was rejected.
On the other hand, reject messages can be useful while developing client
software (I found them indispensable while creating bitcoin-submittx),
as well as for our own test cases, so whatever the default becomes on the
long run, IMO the functionality should be retained as option. But that's
a discussion for later.
