Add support for FreeBSD

[wiz]

I run my headless Bisq nodes on FreeBSD and they all run fine. The only issue is it throws this exception and deletes the Tor key on startup, which is fine for my use case (mempool.space/bisq) but not okay for a seednode or other types of nodes. Can you simply not throw the exception and read the private key exactly the same way you do it on Linux?

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Connecting to Tor successful after 69 ms. Start publishing hidden service.
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Aug-16 02:56:44.231 [NetworkNode-8000] ERROR o.b.n.tor.Tor: could not set permissions, hidden service /bisq/seednode-data/btc_mainnet/tor/hiddenservice will most probably not work java.lang.RuntimeException: Unsupported OS: FreeBSD