Refactor to separate out into components

[stianeklund]

A lot of code can be moved and made into their own component, e.g:

project root/components/EthernetManager/

├── CMakeLists.txt
├── EthernetManager.cpp
└── include
    └── EthernetManager.h

Example CMakeLists.txt:

idf_component_register(
    SRCS "EthernetManager.cpp"
    INCLUDE_DIRS "include"
    REQUIRES
        driver
        esp_eth
        esp_netif
        esp_event
        nvs_flash
        lwip
)```

AFAIK no other changes are necessary aside from adding `REQUIRES` in the `CMakeLists.txt` in `main/`
e.g:

```idf_component_register(
    SRCS
        "main.cpp"
    INCLUDE_DIRS
        "."
    REQUIRES
        freertos
        esp_wifi
        nvs_flash
        esp_http_server
        driver
        esp_netif
        esp_timer
        json
        esp_eth
        i2c_manager
        kc868a16
        ethernet_manager
        pcf8574
        uart_manager
        wifi_manager
)```