Add the ability to create Template Cards

[netsoft-ruidias]

Users should be able to create new template cards and use/reuse them across all dashboards.
This new area will do for dashboards what Blueprints do for "Automations".
Pointing that Blueprints are for backend actions, Templates will help us in the frontend.

how to get this:

1. Rename Settings > Dashboards to Settings > Dashboards & Templates

   1.1. In Settings > Dashboards & Templates create a new "area" (tabs, like the ones in Settings > Automations and Scenes) called Templates.

   ie: Automations and Scenes has tabs: Automations + Scenes + Scripts + Blueprints
Dashboards & Templates should have Dashboards and Templates tabs.

   

   1.2. Once there (in templates) you can create new template cards.

   A template has a single card is its root and some "custom fields"

   The editor can be the same as "Add Card" in the dashboard, but it should alow us the create "custom fields" that we can set later

   If you still don't know, the idea is to allow more or less what we can get with this custom card:
   https://github.com/custom-cards/decluttering-card

   Each card must have a unique name, which will be used later to refer to this card.

2. When we edit a dashboard, we can Add Card. In the Add Card popup we have two options/tabs: "[Add] By Card [type]" or "[Add] by Entity". It should have one more option: "[Add] By Template", like this: "BY CARD | BY TEMPLATE | BY ENTITY"

   

   2.1 The "Add By Template" tab, would show a list of all the templates we created in "settings"

   2.2 The user chooses the template he wants and the editor (like the one for cards) is displayed, with "custom fields" to fill in.

   2.3 Looking at Yaml (for those who want Yaml) the card is called "template" and can be described like any other cards.