* Update IDF to v3.2 977854975

* Update app_httpd.cpp

Fixes https://github.com/espressif/arduino-esp32/issues/2740

* Other Arduino cores uses a macro to redefine libc abs() to take any
  type, meaning abs(-3.3) == 3.3 not the normal libc result of 3.

* 1e4bf14a (#1783) replaced similar min, max macros with c++ stdlib. However
  this change includes <algorithm> after the line which defines the abs() macro.
  <algorithm> includes <cstdlib> which undefines abs() and re-defines it.

* This means abs() becomes the plain libc version again which only takes
  integers, so abs(-3.3) == 3. As reported here:
  https://github.com/espressif/esp-idf/issues/3405

This fix tries to keep in the spirit of #1783 by using libstdc++. The other
option would be to include <cstdlib> before defining the abs() macro, so it
doesn't get undef-ed again later on.

As found by @mongozmaki in https://github.com/esp8266/Arduino/pull/6035

With SSO implementation in String, StreamString::write generates wrong
strings under some circumstances.  Reason is that String::len() returns
strlen(sso_buf) if SSO=true but with newly written data
(in StreamString::write) the null-termination missing at the time len()
is called.

Furthermore, len() is called twice which is inefficient if SSO=true.

* Fix semaphores in IDF & std::string assert 

Fixes the problem of giving a mutex from a callback with the latest IDF. Also addresses an occasional assert that happens when the btc_task callback gives the semaphore and causes an assert due to both cores potentially writing m_owner concurrently.

* Restored m_owner position in wait() as requested

* Reapply assert fix and move setting m_owner in ::give() 

Revert previous revert commit and move setting of m_owner in ::give to before giving the semaphore to prevent race condition possibility.

Implemented the ability to change the ESP32s BLE device address as
according the the BLE specification. This address is used when
advertising the ESP32 over BLE.

fixes: https://github.com/espressif/arduino-esp32/issues/2758

Fixes Arduino.h redefinition errors.

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.

* Ensure that _size is properly set in begin

* NULL check on _data assignment

* Changed _data to malloc in order to catch alloc fails

* Converted EEPROM library to use nvs instead of partition.  Removed eeprom partition from all partition table CSV files.
* Changed variable names, added some comments, formatting as per me-no-dev's requests
* Checks for memory on malloc
* Moved include nvs.h from header to code
* Reworked the extra example to make it more clear how to actually use the library and persist data

* add support for CORS headers

* remove accidental function impl

* rename setCORS to enableCORS, and add aliased function enableCrossOrigin

* Replaced ARDUINO_VARIANT with const char

* Fixed missing return value

* Added quotes around defined value in macro (Issue #2193)

* Change logging from Error to Verbose when not found and default available

* Move Enter and Exit logging to Verbose Level

* Refactored LOG_X() into log_x()

* Add board "SparkFun LoRa Gateway 1-Channel".

* Extend boards.txt.

Source: https://learn.sparkfun.com/tutorials/sparkfun-lora-gateway-1-channel-hookup-guide/all

Fixes: https://github.com/espressif/arduino-esp32/issues/2660

* Set IDF to v3.2

* Remove BLE submodule

* Add BLE lib source

* Update Camera example to support OV3660

* Properly allocate string and remove warning

The former way generates the following warning:
ISO C++ forbids converting a string constant to 'char*'

This change makes a character array the size of the string with null ending. It's clearer and gets rid of the warning.

* Better way

Since this is technically immutable, the type should reflect this too.

* add opportunity for more than one retry to _uploadReadByte

* an alternative timeout-based method to making _uploadReadByte more resilient

* move timing variables in the correct scope

* implement and use client.getTimeout instead of hard-coded timeout in _uploadReadByte

* add missing return

* some refactoring to address respecting the timeout in a potentially deadlocked connection

* fix spelling in comment

* address review comments; move impl to cpp file for getTimeout, and remove local variable for currentMillis

* remove redundant cast

* need to check for timeout outside the inner while as well

* update WebUpdate example to print something in unexpected callback condition

* update log_e messages per review comments