Censorship resistant bootstrapping (e.g. for wikipedia)

#### Version information:
N/A

#### Type:
Enhancement

#### Severity:
Medium (unless you're in Turkey, then High)

#### Description:
I was thinking about the attack vectors for censorship of the recently hosted wikipedia in Turkey, and I believe a significant weak point is the bootstrap process. Currently it is a hardcoded (in a config file) list of domains/ips. This is public and easy for an oppressor to add to a blacklist.

One proposed mitigation to this would be to have a fallback bootstrap method which used Tor. Tor have thought a lot more about attacks in this area, and using them would be easy. The simplest would be a Tor client that just contacts one of the bootstrap nodes through Tor to then bootstrap via. Clearly this is only as strong as the Tor bootstrapping mechanism, but as mentioned above that is a well studied problem.

This would mean that a binary of ipfs that was distributed in Turkey through USB sticks would still work even if ipfs.io and all the public ipfs bootstrap nodes were blacklisted.