* General code cleanup.
* `NimBLEAdvertisementData` moved to it's own .h and .cpp files.
* Added new method, `NimBLEAdvertising::setPreferredParams` that takes the min and max preferred connection parameters as an alternative for `setMinPreferred` and `setMaxPreferred`.
* Added new method, `NimBLEAdvertising::setAdvertisingInterval` Sets the advertisement interval for min and max to the same value instead of calling `setMinInterval` and `setMaxInterval` separately if there is not value difference.
* `NimBLEAdvertisementData` payload is now stored in `std::vector<uint8_t>` instead of `std::string`.
* `NimBLEAdvertisementData::getPayload` now returns `std::vector<uint8_t>` instead of `std::string`.
* `NimBLEAdvertisementData::addData` now takes either a `std::vector<uint8_t>` or `uint8_t* + length` instead of `std::string` or `char + length`.
* `NimBLEAdvertisementData::setName` now takes an optional `bool` parameter to indicate if the name is complete or incomplete, default = complete.
* `NimBLEAdvertising::start` No longer takes a callback pointer parameter, instead the new method `NimBLEAdvertising::setAdvertisingCompleteCallback` should be used.
* `NimBLEAdvertising::setAdvertisementType` has been renamed to `NimBLEAdvertising::setConnectableMode` to better reflect it's function.
* `NimBLEAdvertising::setScanResponse` has been renamed to `NimBLEAdvertising::enableScanResponse` to better reflect it's function.
* Scan response is no longer enabled by default.
* Added new method, `NimBLEAdvertising::setDiscoverableMode` to allow applications to control the discoverability of the advertiser.
* Advertising the name and TX power of the device will no longer happen by default and should be set manually by the application.
* Added overload for `NimBLEAdvertising::setManufacturerData` that takes a `const uint8_t*` and , size_t` paramter.
* Added overload for `NimBLEAdvertising::setServiceData` that takes `const NimBLEUUID& uuid`, ` const uint8_t* data`, ` size_t length` as parameters.
* Added overload for `NimBLEAdvertising::setServiceData` that takes `const NimBLEUUID& uuid`, `const std::vector<uint8_t>&` as parameters.
* All `NimBLEAdvertisementData` functions that change data values now return `bool`, true = success.
* All `NimBLEAdvertising` functions that change data values now return `bool`, true = success.
* `NimBLEAdvertising::setMinPreferred` and `NimBLEAdvertising::setMaxPreferred` have been removed, use `NimBLEAdvertising::setPreferredParams` instead.
* All advertising data is now stored in instances of `NimBLEAdvertisingData` and vectors removed from `NimBLEAdvertising`.
* `NimBLEAdvertising::setAdvertisementData` and `NimBLEAdvertising::setScanResponseData` now return `bool`, true = success.
* Added new method, `NimBLEAdvertisementData::removeData`, which takes a parameter `uint8_t type`, the data type to remove.
* Added new method, `NimBLEAdvertisementData::toString`, which will print the data in hex.
* Added new method, `NimBLEAdvertising::getAdvertisementData`, which returns a reference to the currently set advertisement data.
* Added new method, `NimBLEAdvertising::getScanData`, which returns a reference to the currently set scan response data.
* Added overloads for `NimBLEAdvertising::removeServiceUUID` and `NimBLEAdvertisementData::removeServiceUUID` to accept a `const char*`
* Added new method, `NimBLEAdvertising::clearData`, which will clear the advertisement and scan response data.
