Replacing magic bytes with opcode constants and adding comments
Replacing magic bytes with opcode constants and
adding comments

Signed-off-by: smblucker <d1e1d5dc43f307e95f2c3d95811815016e278606@outlook.com>

eris-ltd/eris-db,silasdavis/burrow,silasdavis/burrow,silasdavis/burrow,eris-ltd/eris-db