Ryman / tor Public

No longer returning zero to keep interval. Functions are expected to always return their intended interval (or a time they want to be polled at).
Now if a precondition fails then it will be polled every second, e.g. servermode is enabled then all server events should be run in the next second.

we skip onionskins that came from non-relays, so we're less likely to
run into privacy troubles.

starts to implement ticket 9658.

Now we explicitly check for overflow.

This approach seemed smarter than a cascade of "change int to unsigned
int and hope nothing breaks right before the release".

Nick, feel free to fix in a better way, maybe in master.

with commit c6f1668 we let it grow arbitrarily large.

it can still overflow, but the damage is very small now.

Conflicts:
	src/test/test.c

Now we consider the TAP cells we'll process while draining the NTor
queue, and vice versa.

that way tap won't starve entirely, but we'll still handle ntor requests
quicker.