Implement HTTP API Client: Devices API

[rnovatorov]

Provisioning:

• Provision Lua Device
• Provision Standalone Device
• Provision vUCM

Fetching Info:

• Get Device
• List Devices
• Get Device Manifest
• Get Connectivity Status
• Get Device Properties
• Get Device Telemetry (latest)

Configuration:

• Get Configuration
• Update Configuration
• Reset All Configuration

Logs:

• Get Logs
• Stream Logs

Commands:

• Execute Command
• Create Command Execution
• Get Command Execution
• List Command Executions