Fixes #1627

Several issues could have been avoided if the example in this PR existed before, e.g. #1630, #1426

Co-authored-by: Louis <spalax@gresille.org>

Fixes #1047
Fixes #527
Fixes #169

Fixes #424

Fixed #1640

Fixes #1652

…ent_from_reader()` (#1613)

Currently, the PdfWriter.pages attribute returns a `DictionartyObject`. With this fix, the attribute will return Iterable[PageObject].

Fixes #1595

See also:
* #1650
* #1654

The error message seen before was:

    ValueError: Incorrect IV length (it must be 16 bytes long)

Fixes #1659

Cope with invalid PDF files where an object can not be found

Fixes #1631

…#1664)

…te: ObjectDeletionFlag) (#1648)

This fixes remove_text to set contents as indirect_objects in accordance with the PDF specification.
It wipes out text in XObject forms as well.

The same issues were fixed for remove_images()

Finally, the new method
    PdfWriter.remove_objects_from_page(page: PageObject, to_delete: ObjectDeletionFlag)
was created. This allows a more fine-granular control of what to delete. It also is easy to expand via the to_delete flag.

Closes #1644
Closes #1650

Add `PdfReader.attachments -> Mapping[str, List[bytes]] as a public interface.

The heavy-lifting was done by @pubpub-zz in #1611 . This PR only adds the interface for the exiting functions.

New Features (ENH)
-  Add reader.attachments public interface (#1611, #1661)
-  Add PdfWriter.remove_objects_from_page(page: PageObject, to_delete: ObjectDeletionFlag) (#1648)
-  Allow free-text annotation to have transparent border/background (#1664)

Bug Fixes (BUG)
-  Allow decryption with empty password for AlgV5 (#1663)
-  Let PdfWriter.pages return PageObject after calling `clone_document_from_reader()` (#1613)
-  Invalid font pointed during merge_resources (#1641)

Robustness (ROB)
-  Cope with invalid objects in IndirectObject.clone (#1637)
-  Improve tolerance to invalid Names/Dests (#1658)
-  Decode encoded values in get_fields (#1636)
-  Let PdfWriter.merge cope with missing "/Fields" (#1628)

[Full Changelog](3.4.1...3.5.0)