Enable Debugging of chutney-launched tor nodes

Set DisableDebuggerAttachment to 0, because if you're running a
test network, you might actually want to use a debugger on tor.
Increase relays to compensate for smaller guard fraction

Since the guard percentage has been reduced from 50% to 25% of relays,
we need more relays to compensate. This patch uses 8 relays, ensuring
at least 2 guards on all known tor versions.
Force authorities to vote Exit & Guard for all nodes

Use the new tor TestingDirAuthVoteExit option, and the
TestingDirAuthVoteGuard option, to make all authorities vote all relays
(and authorities) as exits and guards. This ensures that tor's
make test-network will work. But it's a sledgehammer approach.

Requires either the new tor TestingDirAuthVoteExit option, or the
issue-13161-check-torrc-options patch for chutney.
Create a middle flavour, and size variants for basic and middle

Create a middle flavour, which includes non-exit routers.

Create size variants for basic and middle, with 25 and 100 tor nodes.
As these variants get larger, approximate the proportions of the global
tor network.