This is a generic function to perform various alignments, this avoids reinventing
locally the magic alignment dance and reusable for consumers who may themselves align things.

This is a simple function to assemble a template section table with
zeros in the unpredictable fields, it's up to the caller to carry on the
fill procedure, e.g. a writer structure which can do the layout.

It can automatically set the virtual address and size based on another
binary to append it, only the on-disk offsets are left to the caller.

Previously, we were handling the offset ourselves, but we can just use `gwrite_with`
to let the offset be moved.

We don't need to use the "read" offset, this is only a distraction and can get wrong results
sometimes.

We only need to write in the order and assume linearity.

It is now easy to peek into the data of a data directory and list all
directories with their originally parsed offsets.

> 216/232  8 Reserved, must be zero

According to the table mentioned in https://learn.microsoft.com/en-us/windows/win32/debug/pe-format#optional-header-data-directories-image-only
In the past, we returned errors in case they were present.

Relative virtual address to disk offset is a classical operation to
perform for various things, it is likely this operation won't change and
if it changes, we can keep it around and deprecate it quite easily in
the next release.

An example for external consumers: compute debug directory data offsets
from RVAs to write a debug directory.

- derives additionally `Debug` on it for logging
- derives additionally `Pwrite`, `SizeWith` for good developer
  experience with scroll on it
- provides a natural type alias in accordance with `WIN_CERTIFICATE` name

We forgot those but they come handy in the UEFI ecosystem when you are
reading UEFI signature lists.

There's no reason to render it as private, this enable a user to peek inside
the raw structure and perform more complicated reading without holding
the original bytes around.

Nonetheless, we expose it via a function to make it easier to deprecate
it or modify as we need.

It can be hard to debug why your writer is not working as intended, here
are some `debug!` traces to help in that endeavor.

…e certificates

It's possible that a user may pass an improperly created attribute certificate
and the write will cause all sorts of failure.

We sprinkle some `debug_assert!` to avoid this.