Attempting to make it more clear to users (particularly hass.io users) that the gactions cli can be run from any pc. Replaced "install" with "download" and a few other changes.
A few people have got lost by not adding the config (since it isn't explicit when you need it by). Added a new step 8 to point out that you have to have it in by now or you can't continue.
* Language clarification
Made it clearer that in 4.2 the client_id is the same as used before. Existing language is unclear and suggests that making them the same is optional.
* Also added clarity on the sync service
* Add new configuration variables for request_sync
* Update google_assistant.markdown
Include note about initial sync with agent_user_id
* Change to api_key - remove homegraph prefix
* ✏️ Small spelling/grammar fixes
* Add google_assistant component
* Be more explict about config keys and replaced strings
* Fix typo and minor language change
* Some minor spelling & grammar fixes
