Replace current win32 poll emulation function with another one with an open domain license from the libressl-portable project.
It was brought to our attention that the current function was derived from VLC's code and the LGPL license on it is not compatible with our BSD2 license.

If more than 5 packets do not decode into a correct header, disable
processing of further packets until we receive a new NONCE for this
connection. This should prevent garbage data from being processed.

This is needed to fix an issue whereby sender is configured as a client
and after authenticating the receiving server the receiving server is
re-configured wrt it's EAP authentication and sender does not detect this.

This fixes an issue whereby a sender is configured to connect outbound without credentials
while the receiver (in server mode) is configured to request them. This would put the sender
in a permanent failure state, where it cannot send data to the receiver, even if the receiver
configuration was changed to not require credentials.

Use libtool rules (& fix current versioning) for library, use semver for API

Timeout time could be smaller than configured buffer, if we stop
sending packets at all in the meantime that would be a guaranteed
discontinuity.

Fixes #108

This reverts commit 30570370.

This was already fixed in 975750b8

I should've paid more attention :/

Fixes #107

Fixes #105

When starting with no peers peerlist_lock is being held for very long times when
adding peers. In fact it's not being held but being reacquired so fast that the
calling application sits waiting a long time before it's able to add a peer.

This really shouldn't have been part of the container, fixing it because
wrong values are worse and it cannot be removed without breaking ABI.

../src/udp.c:47:54: runtime error: left shift of 2209677876 by 32 places cannot be represented in type 'long long'
&& ../src/udp.c:63