* adding optional mmr index to key ids
* rustfmt
* update index
* add mmr index to output display
* change restore to match on commit instead of ID, add extensive restore/check tests for multiple wallets using same seed
* rustfmt
* ensure check restores unknown accounts as well
* rustfmt
* remove storage of commit from wallet
* add feature for height locked kernels
* add function to compute kernel features appropriate for lock height, and use it
* only sign kernel-features relevant fields; refactor Features
* simplify invalid kernel logic
* remove unused height arg to reward::output and run some rustfmt
* replace nested if/else by match
