* travis: move build flags tests outside of hardware header

* mqtt: fix typo

* travis: use files instead of bundling test cases into script

* fixup! travis: use files instead of bundling test cases into script

* fix variable expansion, remove custom h at the end

* add ade7953 to sensors list

* custom.h path as variable

* shellcheck

* fix printf syntax, silent again

* fix bash 4.3 treating empty array as unset variable

* telnet: buffered output for async server

* telnet: make async buffer an option

* just use the queue containers directly

* try with simpler list

* exhaust buffers as much as possible in a single try

* don't forget to destroy the client object

* naming

* kill the connection earlier

* fix merge issues

* MQTT rewrite with SSL fixes

- Added Arduino MQTT library support (actively maintained)
- Added support for BearSSL (core >= 2.5)
- BearSSL validation: insecure, fingerprinting and CA validation
- AxTLS validation: insecure and fingerprinting
- Support MFLN in order to reduce heap usage

* Better header incl, fix building w/ no NTP_SUPPORT

* Clean up code, use DEBUG_MSG_P

* Fix compile error

- add httpupdate ota impelementation
- move async ota into a separate module
- support bearssl & axtls through wificlientsecure
- allow to disable arduino ide ota module

Isolated dependencies

sensors dependencies

enums, macros and prototypes.

I2C dependencies moved to actual sensor files.

definitelly redefine