feat/ovos_backend

[JarbasAl]

follow up to #10

OVOS Backend Api

Python client library for interaction with several supported backends under a single unified interface

• Personal backend - self hosted
• Selene - https://api.mycroft.ai
• OpenVoiceOS API Service - https://api.openvoiceos.com
• Offline - support for setting your own api keys and query services directly

Backend Overview

API	Offline	Personal	Selene	OVOS
Admin	yes [1]	yes	no	no
Device	yes [2]	yes	yes	yes [4]
Metrics	yes [2]	yes	yes	yes [4]
Dataset	yes [2]	yes	yes	yes [4]
OAuth	yes [2]	yes	yes	yes [4]
Wolfram	yes [3]	yes	yes	yes
Geolocate	yes	yes	yes	yes
STT	yes [3]	yes	yes	yes
Weather	yes [3]	yes	yes	yes
Email	yes [3]	yes	yes	yes

[1] will update user level mycroft.conf
[2] shared json database with personal backend for UI compat
[3] needs additional configuration (eg. credentials)
[4] uses offline_backend functionality