* Only direct invocation of cypto_hash_sha256 & crypto_hash_sha512 produced correct output.
* Some remaining header file mixups, so changed approach to wrapping the state structures.
* Fixes https://github.com/espressif/esp-idf/issues/1044 (crypto_sign problems)
* Add option to disable mbedTLS implementation for SHA256 & SHA512 in libsodium
Currently libsodium tests add about 800kB to the binary, which is too
much for a partition table constrained to 2MB. Disable libsodium tests
until we start building multiple unit test apps for different subsets.
Run some unit test cases based (poorly) around sodium's test infrastructure.
Increase in unity test task stack is due to signature tests, load a lot of data onto the stack.
