* Add threading support to SGX Avian.
* Handle contract verification exceptions using uncaught exception handler.
* Indent uniformly to 4 spaces.
* Add comments for some of the uses of SGX synchronisation primitives.
* Update SGX build to use deterministic OpenJDK repository.
* Remove unused imports.
* Update Kotlin dependencies.
* Update Avian so that it compiles against our OpenJDK repo.
Also include sunec.jar in the Avian binary. because the Enclavlet needs it.
* Embed jsse.jar within Avian to enable X.509 support.