histedit: directly use node in 'verifyactions' It does not seem useful to convert to hex: it is an extra step and they are longer strings. So we stick to node for the logic. We only convert to short hex for error when needed. As a nice side effect this remove the explicit constant usage in'[12:]'. This will also help moving the code around later as we just have to access action.node.

histedit: temporarily shorten name of 'constraints' variable An upcoming changeset will make the line where this variable is used slightly too long. Other later changesets will clean that up further and makes the variable unnecessary, so this is only temporary and it does seems useful to put anything more complicate in place.