Upgrade tor to 0.3.4

https://trac.torproject.org/projects/tor/wiki/org/teams/NetworkTeam/CoreTorReleases#Listofreleases says it’ll be released as stable on 2018-08-15.

Feature Branch: feature/15770-tor-0.3.4

Related issues

Blocks #15334 (closed)
Blocks #15772 (closed)

Original created by @intrigeri on 15770 (Redmine)

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