Show example with states with on_enter

[spuder]

Thank you so much for this esphome component.

As a new user, I've been struggling to get a basic example working. I continued to get this error:

      Must be string, got <class 'esphome.helpers.OrderedDict'>. did you forget putting quotes around the value?.

The reasoning wasn't clear to me until I found this gist for a garage door opener.

Basically the states can be either

state_machine:
  - name: Fan Mode
    states:
      - NORMAL
      - SILENCED

or

state_machine:
  - name: Fan Mode
    states:
      - name: NORMAL
        on_enter:
          - logger.log: "Fan is turned off"
      - name: SILENCED
        on_enter:
          - logger.log: "Fan is turned on"

However, you can not do the following (which is what I was mistakenly doing)

state_machine:
  - name: Fan Mode
    states:
      - id: NORMAL
        on_enter:
          - logger.log: "Fan is turned off"
      - id: SILENCED
        on_enter:
          - logger.log: "Fan is turned on"

It may be obvious to others, but It wasn't clear to me that states needs either a list of strings, or a list of dictionaries with key 'name'. An additional example in the readme may be helpful for others.