Updated CRT library, test process, EventLoopGroup API updates (#16)

* 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

builder.json

@@ -32,6 +32,6 @@
         "NO_INTERACTION": "1"
     },
     "test_steps": [
-        ["make", "test-ci"]
+        ["make", "test"]
     ]
 }