v1.17.1

• Fix ElectionSize type (Thanks to https://github.com/arjanz)
• Allow BTreeSet decoding from Array/JSON inputs
• Adjust Call-only metadata output to trim documentation to first full line
• Safeguard against divide-by-zero for total era points (expired reward eras)
• Internal derive optimizations with combining calls
• Support for latest Substrate types & metadata
• @polkadot/util 2.12