Add iterators for NimBLEScan: NimBLEadvertisedDevice, NimBLEClient: NimBLERemoteService, NimBLERemoteService: NimBLERemoteCharacteristic and NimBLERemoteCharacteristic: NimBLERemoteDescriptor
This is handy e.g. for showing every address of the advertised devices from a scan. To do so, first get a new scan and next:
```
for(auto pAdvertisedDevice: pBLEScan->getResults()) {
Serial.printf("Address is %s\n", std::string(pAdvertisedDevice->getAddress()).c_str());
}
```
Of course any other property of the advertised device can be shown (or looked up, if that is your use case)
Also this is handy e.g. for showing every UUID in a peripheral. To do so, first connect to a peripheral and next:
```
for(auto pService: *pClient) {
Serial.printf("Service UUID is %s\n", std::string(pService->getUUID()).c_str());
for(auto pCharacteristic: *pService) {
Serial.printf("Characteristic UUID is %s\n", std::string(pCharacteristic->getUUID()).c_str());
for(auto pDescriptor: *pCharacteristic) {
Serial.printf("Descriptor UUID is %s\n", std::string(pDescriptor->getUUID()).c_str());
}
}
}
```
Again of course any other property can be shown, or looked up.
* Exchange map for vector, saving 1,076 bytes of program memory and 5,024 bytes of heap for a small device (LYWSD03MMC)
* Removing m_characteristicMapByHandle (using the handles form m_characteristicVector instead) saving in total (compared to the current master) 1,508 bytes of program memory and 6,500 bytes of heap for a small device (LYWSD03MMC)
* Change NimBLEScan container from std::map to std::vector
* Add function to get advertised device by address
* Update documentation
Previously we used createServer() to get a reference to the server instance.
This was problematic when using advertising only as it would create a server
when starting advertising. This prevents that and provides better semantics.
This allows NimBLE options in menuconfig to reduce code size based on
the roles selected (scan/advertising/central/peripheral).
Significant code space can be saved by removing unnecessary roles for the application.
