1. The head line should contain no more than 72 characters
2. head line is composed by scope : subject
3. multi-scope is supported, separated by a space, such as scope1 scope2 scope3: subject it is better that scope number =<3 , scope length <= 20 char , but not mandatory
4. keyword, such as R4R or WIP is not acceptable in the scope, no matter upper case or lower case.

evm: optimize opcode mload

rpc core db: refactor the interface of trie access

if the change is too big, impact several scopes, the scope name can be bep, feat or fix

bep130: implement parallel evm

feat: implement parallel trie prefetch

fix: stack overflow on GetCommitState