raw Externalities HashMap write

gistfile1.txt

pub type SgxExternalities = HashMap<Vec<u8>, Vec<u8>>;

...

let mut ext = SgxExternalities::new();	

...

//custom struct
let key = runtime_io::twox_128("Contract Schedule".to_vec());
let value = Schedule::<Gas>::default().encode()

ext.insert(key.to_vec(), value)

...

// primitive Type
let key = runtime_io::twox_128("Contract BlockGasLimit".to_vec());
let value = 10_000_000u64.encode()

ext.insert(key.to_vec(), value)

// key "Contract BlockGasLimit" is
twox_128 of [43, 6f, 6e, 74, 72, 61, 63, 74, 20, 42, 6c, 6f, 63, 6b, 47, 61, 73, 4c, 69, 6d, 69, 74]
// writing 0u64.encode() to that key results in raw:
[0, 0, 0, 0, 0, 0, 0, 0]