MQTT5 developer preview support

Note: MQTT5 support is currently in developer preview. We encourage feedback at all times, but feedback during the preview window is especially valuable in shaping the final product. During the preview period we may make backwards-incompatible changes to the public API, but in general, this is something we will try our best to avoid.

What's Changed

• Update CI to fix downstream build by @waahm7 in #225
• MQTT5 support by @TwistedTwigleg in #227
• Fix zip and update canary time by @TwistedTwigleg in #228
• Update canary comment to trigger CI by @TwistedTwigleg in #229
• Add developer preview notice for MQTT5 at top of all public header files by @bretambrose in #230
• Sizet stats by @bretambrose in #231

New Contributors

• @waahm7 made their first contribution in #225

Full Changelog: v0.7.13...v0.8.0

v0.7.13

What's Changed

• Add AppVerifier to CI by @TwistedTwigleg in #222
• Log the client id going into the connect packet by @bretambrose in #223
• Serialize mqtt by @bretambrose in #224

New Contributors

• @TwistedTwigleg made their first contribution in #222

Full Changelog: v0.7.12...v0.7.13

v0.7.12

What's Changed

• Minimum stable connection time before resetting reconnect timer by @sbSteveK in #212
• load cmake target fallback by @TingDaoK in #218
• Infinite loop by @sbSteveK in #219
• removed forced cleansession behavior on a user called disconnect by @sbSteveK in #220

Full Changelog: v0.7.11...v0.7.12

Improve clean up on user disconnection

What's Changed

• Update to latest builder by @bretambrose in #209
• Fixed endpoint not being read in arguments by @sbSteveK in #211
• No resubscribe by @bretambrose in #215
• Clean up on user disconnect by @sbSteveK in #216

New Contributors

• @sbSteveK made their first contribution in #211

Full Changelog: v0.7.10...v0.7.11

Remove using of try_lock

• Try lock is not available in Windows Server 2008. Remove it from our debug build

Empty payload fixes

• Fix a crash on Windows when the will payload was empty (precondition is turned into a fatal assert on Windows CD builds still)
• Fix a decode error when receiving a message with an empty payload

Stability fix

• Fixes a crash due to a race condition in the mqtt connection logic

Allow for null on-message callbacks in subscribe

• Fixes a crash when the on-message callback is null for a subscription
• Updates the public API documentation with some missing parameters and annotations as to what parameters can be null

Data race fixes

• Fixes several data races related to the outstanding requests table and a request's timeout task.

Fix non-threadsafe hash-table accesses (take 2)

v0.7.5

fix test function (#190)