## Summary
Applies the upstream changes here: https://github.com/arduino/ArduinoCore-API/compare/3b88acac8%5E...0d83f1afc3367037dbde5323c2abd0ae1bd2c583
## Impact
Adds new String convenience methods that are now available in the mainline Arduino implementation, simplifying interoperability with C code that uses pointer+length strings rather than 0-termination. Also includes a change to avoid mutating the source string when taking a substring.
* Make String::concat() faster for some types.
This patch removes the unneeded call to `strlen()` when concatenating some types to a `String`. Additionally it fixes some whitespace for consistency.
* Update WString.cpp
I redid the ESP8266 WString library to enable small string optimization
(SSO) a while back, and think it would be helpful even on the ESP32 with
its higher memory complement.
SSO avoids lots of tiny mallocs() on the heap which cause fragmentation
by using the memory in the class object itself to store the actual
string and only mallocing() for buffers that are larger than what can
fit in thie class object. Modern C++ std::string implementations have
this optimization as well, but since we're using Arduino strings we had
to roll our own.
* fix sdmmc config
* Fix warnings in EEPROM
from @Curclamas
* remove leftover TAG in EEPROM
* Initial add of @stickbreaker i2c
* Add log_n
* fix warnings when log is off
* i2c code clean up and reorganization
* add flags to interrupt allocator
* fix sdmmc config
* Fix warnings in EEPROM
from @Curclamas
* remove leftover TAG in EEPROM
* fix errors with latest IDF
* fix debug optimization (#1365)
incorrect optimization for debugging tick markers.
* Fix some missing BT header
* Change BTSerial log calls
* Update BLE lib
* Arduino-ESP32 release management scripted (#1515)
* Calculate an absolute path for a custom partitions table (#1452)
* * Arduino-ESP32 release management scripted
(ready-to-merge)
* * secure env for espressif/arduino-esp32
* * build tests enabled
* gitter webhook enabled
* * gitter room link fixed
* better comment
* * filepaths fixed
* BT Serial adjustments
* * don't run sketch builds & tests for tagged builds
* Return false from WiFi.hostByName() if hostname is not resolved
* Free BT Memory when BT is not used
* WIFI_MODE_NULL is not supported anymore
* Select some key examples to build with PlatformIO to save some time
* Update BLE lib
* Fixed BLE lib
* Major WiFi overhaul
- auto reconnect on connection loss now works
- moved to event groups
- some code clean up and procedure optimizations
- new methods to get a more elaborate system ststus
* Add cmake tests to travis
* Add initial AsyncUDP
* Add NetBIOS lib and fix CMake includes
* Add Initial WebServer
* Fix WebServer and examples
* travis not quiting on build fail
* Try different travis build
* Update IDF to aaf1239
* Fix WPS Example
* fix script permission and add some fail tests to sketch builder
* Add missing space in WiFiClient::write(Stream &stream)
Previous __FlashStringHelper implementation was defines as a char which brought problem in case the method with char* parameter used overloading with __FlashStringHelper* parameter (they was identical). Now __FlashStringHelper is defined as a class and all casts between char* and __FlashStringHelper* are made with reinterpret_cast sugar.
