Add chutney support for FallbackDirs
Just like chutney adds DirAuthority lines, it should add a FallbackDir line for each relay / exit. This will allow us to test legacy/trac#15775 (moved) / legacy/trac#4483 (moved).
Just like chutney adds DirAuthority lines, it should add a FallbackDir line for each relay / exit. This will allow us to test legacy/trac#15775 (moved) / legacy/trac#4483 (moved).