[DeviceStruct] Add PinDirection flag for PIN1..PIN3

[tonhuisman]

Feature:

• Add Pin1Direction..Pin3Direction flags to DeviceStruct so each pin (based on the Device[].Type field) can be configured in the correct direction. This is to stop input-only pins to be selected for output use.
• Not applicable to Serial Types (Pin1/Pin2) and SPI Types (Pin1..3).

Example:

Device[deviceCount].Pin1Direction = gpio_direction::gpio_output;

With this added to the Plugin device definition, only GPIO pins with output capability can be selected.

TODO:

• [x] Testing (tested locally)