John Wellbelove

Add `constexpr` to `etl::variant`

Add the ability to use builtins for type traits if they exist.

As exceptions are not normally used in embedded code, changing to using an error handler in the unit tests will better match real code use.

The internal constants and template non-type parameters in the ETL are mostly all uppercase, which can easily clash with macro name definitions. Change the case to initial capitals and underscores....

Replace all usage of `etl::function` within the ETL and related classes with `etl::delegate`.

Approximate clone of `std::chrono`

Change unit test framework to Google Test

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The current UnitTest++ framework no longer appears to be maintained and the ETL's fork has been customised to update it to be compatible with current C++ versions. I propose updating...

[LIB REQUEST]: Add Embedded Template Library (ETL)

1

### Library name ETL ### Library description The Embedded Template Library is a C++ STL like library tailored for embedded projects ### Library repository https://github.com/ETLCPP/etl ### Motivation It is a...