implement web3 personal API

[noot]

Proposal: [Description of the feature]

implement personal ethereum api: see https://geth.ethereum.org/docs/rpc/ns-personal

• personal_importRawKey
• personal_listAccounts
• personal_lockAccount
• personal_newAccount
• personal_unlockAccount TODO: use duration
• personal_sendTransaction
• personal_sign
• personal_ecRecover

Current behavior: [What currently happens]

Desired behavior: [What you would like to happen]

Use case: [Why is this important (helps with prioritizing requests)]

Requests may be closed if we're not actively planning to work on them.