NVS examples
Add two examples for working with NVS.
One is reading and writing an integer value, another is reading and writing a blob.
See merge request !194
Updated previusly submitted example, saved it as "07_nvs_rw_value" and
added a new one.
Overview of examples:
* 07_nvs_rw_value - simple read and write a single value
* 08_nvs_rw_blob - read and write a blob that is extened with new data
on each restart of ESP32
Removed LICENSE files
Demonstrates how to read and write a value using NVS.
The value tracks number of ESP32 module restarts.
Example also shows how to use basic diagnostics if read / write
operation was successful.
This change removes implicit WiFi/BT initialization from startup code.
"main" task is started once essential part of startup code is complete.
This task calls application-provided "int main(void)" function, which can call WiFi/BT init functions if necessary.