v0.7.1

• Refactor Transaction Requests to JSON-RPC call requests
• Add sendTransaction / signMessage / signTypedData methods
• Refactor Session Requests on establishing connection
• Add approveSession / rejectSession / killSession methods
• Expose connected boolean to verify established connection
• Expose listener to stop short-polling
• Expose toJSON method for storing sessions
• Generate JSON-RPC payloads for call requests
• Refactor Push Notification data to support others: fcm, apn, gcm, etc
• Add walletconnect-web3-subprovider package
• Add walletconnect-qrcode-modal package