Fix for dangling port forwards

Code tears down the port forwards prior to migrating so that we don't end up with dangling connections that don't work.
Add code to recreate the forwards after migration

* Feels like a bit of a hack job, but it works.
Remove unncessary counter var
Disambiguate tape_engine_8A as tape_engine_0x8a

This will reopen #2358 to avoid filename collisions on Windows, Rubymine
environments, etc.
Merge pull request #1 from todb-r7/land-2414

Disambiguate tape_engine_8A as tape_engine_0x8a
Idiomatic Ruby

Assuming this gets accepted, this should [FixRM #8240]. Take a look, and
if you're good with it, I'll land on master. Everything seems to work
out on this end.
Merge remote-tracking branch 'todb/land-2414' into migrate_close_channels
Land #2414, portfwd teardown and recreate

[FixRM #8240]