Release 9.1.0

This release adds support to the Soroban smart contract operations.
Please update your library to the latest version (9.1.0) to prevent any breakage that might occur when Soroban goes live on the Public Network 30th January.

Breaking Change

• Renamed class Signer to SignerUtil.

What's Changed

• Added complete unit tests for SorobanAuthorizationEntry, InvokeHostFunctionOperation and SCVal objects by @cuongph87 in #2
• Added support for LedgerEntry classes, SorobanResources and SorobanTransactionData by @cuongph87 in #3

New Contributors

• @cuongph87 made their first contribution in #2

Full Changelog: 9.0.54...9.1.0