The MemoBytes struct is a minimal wrapper around the memo bytes, and only
imposes the existence of null-padding for shorter memos. The only error
case is attempting to construct a memo that is too long. MemoBytes is
guaranteed to be round-trip encodable (modulo null padding).
The Memo enum implements the additional memo rules defined in ZIP 302,
interpreting the contents of a memo (for example, parsing it as text).
Also move dependency on params out of wallet read/write methods.
The result is cleaner because these parameters are only required
for backend-specific encoding and decoding operations.
This required changing a bit about the relationship between
database errors and wallet errors, and opens up the possibility
of now simplifying the error situation a bit.
In the interest of making the library usable for both
testnet and mainnet without recompilation, static resolution
of network parameters has been replaced with a parameter passed
to the relevant functions. This also moves addres prefix constants
into the network parameters.
Jack Grigg
Kris Nuttycombe