Save accounts to:
/etc/letsencrypt/accounts/www.letsencrypt-dmeo.org/acme/new-reg/ \
kuba.le.wtf@2015-07-04T14:04:10Z/ \
{regr.json,meta.json,private_key.json}
Account now represents a combination of private key, Registration
Resource and client account metadata. `Account.id` based on the
account metadata (creation host and datetime). UI interface
(`cli._determine_account`) based on the `id`, and not on email as
previously.
Add `AccountStorage` interface and `AccountFileStorage`,
`AccountMemoryStorage` implementations (latter, in-memory, useful for
testing).
Create Account only after Registration Resource is received
(`register()` returns `Account`).
Allow `client.Client(..., acme=acme, ...)`: API client might reuse
acme.client.Client as returned by `register()`.
Move report_new_account to letsencrypt.account, client.Client.register
into client.register.
Use Registration.from_data acme API.
achallenges.AChallenge.key is now the `acme.jose.JWK`, not
`le_util.Key`. Plugins have to export PEM/DER as necessary
(c.f. `letsencrypt.plugins.common.Dvsni.get_key_path`)
Add --agree-tos, save --agree-eula to "args.eula". Prompt for EULA as
soon as client is launched, add prompt for TOS.
Remove unnecessary letsencrypt.network. Remove, now irrelevant,
`IConfig.account_keys_dir`.
Based on the draft from
https://github.com/letsencrypt/letsencrypt/pull/362#issuecomment-97946817.
