BUMP: update rusm to the upstream compiler

* Change Eq to PartialEq
BUMP: update rusm to the upstream compiler

* Remove std::num::Bitwise
Remove support for qemu-arm.

Only run the test suite when natively building for ARM.
BUMP: Update rusm to the upstream compiler

* rustc no longer generates a hash for libraries
BUMP: update rusm to the upstream compiler

* New syntax for attributes: #![name(value)]
* No more ambiguities for signed/unsigned immediates
* MemoryMap: len and data are now methods
* extern crate std is automtically imported
* Fixed a borrowing issue in the ARMAssembler
* Casting raw pointers to a Rust function is now forbidden: this patch removes
  the current API for calling generated code, this is a work in progress
Massively refactor tests

The macro test_emit! now assembles and calls the generated code. To then return
the result.
Rename Function to CodeBuffer

The idea is to take advantage of overloading the call operator in the future
with the Fn trait.