Remove PGP encryption requirement.

[jholdstock]

Several reasons for this:

• It is abnormal to require encryption. From my research almost all large bounty programs have optional encryption and do not punish for not using it.
• It was very rarely used (I guess about 1 in 25 reports encrypted).
• Admin overhead of maintaining up to date keys and sharing keys among bug bounty group is not worthwhile.
• Decrypting reports which are encrypted using different tools/formats is time consuming. Often an extra email or two are required where the reporter has not encrypted properly.
• Encryption can still be arranged on a case-by-case basis when it is desirable.

[davecgh]

I personally prefer having it because e-mail is all plaintext and super insecure, but you're managing the program, so I'll defer to your judgement there.

Either way, the updates which look fine, so I'll approve it as that has nothing to do with the policy side.