Create area entity

[mvgijssel]

• [x] Ability to configure rooms through the config (https://github.com/vgijssel/setup/pull/648)
• [x] Room is represented by a select input (https://github.com/vgijssel/setup/pull/648)
• [x] For each state transition expose a timer
• [x] When an attached door has presence, change to entering
• [x] When door has activity while entering, extend the timer
• [x] While entering check if human presence sensor detects anything
• [x] If human presence sensor detects move into confirming_enter
• [x] For a predefined time expect the human sensor to be active
• [x] If this is the case move into present
• [x] When an attached door has presence, change to leaving
• [x] While leaving check if human presence sensor detects nothing
• [x] If human presence doesn't detect move to confirming_leave
• [x] During a set time if still no presence is detected move to absent