Direct mqtt through http proxy

• Adds support for establishing direct mqtt connections through an http proxy

safely MQTT publish

• Underlying lib will keep the payload alive, now, the payload of publish doesn't need to be alive until the complete callback

aws-lc

This release simplifies the build process.

• SDK uses libcrypto from included aws-lc submodule. Previously, Linux users needed to compile and install install libcrypto from OpenSSL in a specific way.

• CMake option BUILD_DEPS is now ON by default, simplifying the configuration for most users.

Improved proxy support

• Refactor of existing proxy systems
• • Tunneling vs. forwarding is an explicit configuration choice, and no longer implicit based on tls properties. The behavior of existing applications should remain unchanged.
• • Implemented a new proxy "strategy" system for authentication. Strategies exist for no authentication, basic authentication, and synchronous strategies are now in place to support kerberos and ntlm authentication. Strategies can be linked together in a chain and attempted sequentially. Existing authentication controls remain in place but are deprecated and now map to the new strategy types.

Fix esoteric build scenarios

• Fix shared-lib builds of inner submodules
• Fix building tests of inner submodules

Fix inner submodules

• Fix some inner submodules that got synced to an old commit

Safer shutdown

• transitions to new managed thread join system, allowing user code to be certain that all CRT threads have been completely joined

MQTT on-message callback carries more info

• Alternate callback allows user to know qos retain and dup of received MQTT messages

Numa fix + iot symbol export updates

v1.10.5

Submodule update for internal import and numa fixes (#233)

Address issues writing large payloads with MQTT/websockets

• Fix error which surfaced when writing large payloads over secure websockets (and MQTT over websockets)