Raptorq

BREAKING CHANGE: Fix the assignment of `PayloadId` to match RFC6330

* Rename `new2()` to `new()` and `with_encoding_plan2()` to `with_encoding_plan()` to replace deprecated functions

* Fix misaligned pointer error on ARM

* Support no_std environments
* Fix panic when generating packets with size < 32 bytes

* NEON optimized code path on aarch64 no longer requires nightly

* Make extended_source_block_symbols() public

* Fix panic when decoding certain combinations of repair packets