* General code cleanup and rename variables to use a consistent style.
* Removes the disconnect timer and will use the BLE_GAP_EVENT_TERM_FAILURE event to handle failed disconnects.
* `NimBLEClient::getConnId` has been renamed to `getConnHandle` to be consistent with bluetooth terminology.
* `NimBLEClient::disconnect` now returns a `bool = true on success` instead of an int to be consistent with the rest of the library.
* `NimBLEClient::setPeerAddress` now returns a bool, true on success.
* `NimBLEClientCallbacks::onConfirmPIN` renamed to `NimBLEClientCallbacks::onConfirmPasskey` to be consistent with bluetooth terminology.
* `NimBLEClient::setDataLen` now returns bool, true if successful.
* `NimBLEClient::updateConnParams` now returns bool, true if successful.
* `NimBLEClient::getServices` now returns a const reference to std::vector<NimBLERemoteService*> instead of a pointer to the internal vector.
* Sets macros to allow compiling when Central role is enabled and Observer disabled, or Peripheral enabled and Broadcaster disabled.
* Adds a macro definition for CONFIG_NIMBLE_CPP_IDF to enable different include paths/functionality for IDF / Arduino.
* Replace all semaphores with task notifications.
* use critical sections to prevent concurrent data access.
* Ensure scan stop has been called before connecting.
* Optimize and cleanup
* Add template casting to NimBLERemoteDescriptor::readValue()
* Removed storage of the descriptor value read as it did not serve any purpose.
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.
