don't exit when tor binary check fails

[jo285317]

Make Tor a soft dependency, cope gracefully if tor hangs #2211

This doesn't break the app, as platforms.BINARIES.Tor will be still be false, and thus there will be no way to attempt to load tor.

[BjarniRunar]

Thank you for doing this!

I'll try and review the functionality soon, and get it merged if I don't find any show-stoppers.

In the meantime (and this is optional), it would be helpful if you could remove your use if the Python warnings. I realize we're probably lame for not using them, but they're not currently used anywhere else in the code and I would rather we avoid a proliferation of different logging strategies within the app. Switching to more standard Python logging would probably make sense, but it needs to happen in a coherent way, not like this.

If you don't find the time, I'll be stripping that stuff out myself when I merge.

Thanks again!