[evm] performance: since we only create a cacheCtx whenever a precompile is called, then reverting a precompile call can just get rid of the cacheCtx and reset the writeToCommitCtxFromCacheCtx function to nil. That would be a cleaner way to revert a PrecompileCalled journal entry rather than deep copy the multistore and save it in a snapshot, but I'd have to test that implementation out.

[evm] performance: since we only create a cacheCtx whenever a precompile is called, then reverting a precompile call can just get rid of the cacheCtx and reset the writeToCommitCtxFromCacheCtx function to nil. That would be a cleaner way to revert a PrecompileCalled journal entry rather than deep copy the multistore and save it in a snapshot, but I'd have to test that implementation out. #42