* Net gas metering for SSTORE without dirty maps
* typo: opcode
* typo: changed
* Self-assign the PR number 1283
* Add a dummy discussion url
* Fix R_sclear loopholes
* Properly handle refund for 0 value issue
* fix: refund should only be added again if new value is 0
* clarify if statement
* Clearly state what () means
* typo fix: unnecessary wording "additional"
* fix: should have parent clause if original value is not zero
* Remove 15k gas from refund counter instead of deduct it as gas cost
* Be more clear on EIP-658 enabled only-commit-storage-changes-at-end-of-block optimizations
* Move some discussion comments to motivations section
* typo: commons -> common
* Be more specific when gas reduction won't happen compared with EIP-1087
* typo: duplicate description
* Add explanation section
* becomes -> become
* typo: covers -> cover
* Add state transition diagrams
* Fix table formatting
* typo: 0 -> `current`
* typo: missing -
* Change state transition table to use `(current, original)` vs `new`
* fix: vertical <-> horizontal
* Be more specific on usages benefited by this EIP
* Typo fix
Wei Tang