Source code license

[ge0rg]

Hi Rui,

I stumbled upon your very nice introduction and wanted to use the ESP32-CAM-Take-Photo-Save-MicroSD-Card example for my own (FOSS) little project. The license in the source file is missing a few words on what's actually allowed, and it would be even better if you could explicitly specify which license applies to the source code, and if it was one of the established FOSS licenses.

Thanks!