* Updated to latest aws-crt-ffi, updated EventLoopGroup/options init
* Removed test-ci target, just use test for everything now
* Added event_loop_group API to CRT/stubs
* Removed headers (all generated) from format-check
* Added the ability to force extension vs FFI
* make test will now trigger composer run test/phpunit, and force tests with both FFI and extension
* Updated builder version, removed redundant php7 test run
* Removed type annotations that anger php5, limited backends on php5
* Added awscrt_version() and test for it
* Added builder.json for CI
* Added github actions
* Added format-check.sh
* Force php5.6 on ubuntu
* Updated submodules