Allow Xlsx Reader to Specify ParseHuge Release1291

[oleibman]

Backport #4514. A number of Security Advisories related to libxml_options were opened. In the end, we disabled the ability to specify any libxml_options. However, some users were adversely affected because they needed LIBXML_PARSEHUGE for some of their files. Having finally obtained access to a file demonstrating this problem, we can restore this ability.

• The operation is potentially dangerous, a vector for memory leaks and out-of-memory errors. It is not recommended unless absolutely needed.
• It will not be permitted as a global (static) property with the ability to adversely affect other users on the same server.
• It will instead be implemented as an instance property of Xlsx Reader (default to false), with a setter. I do not see a use case for a getter.
• People will need to set this property individually for each file which they think needs it.
• This change will be backported to all supported releases.
• The sheer size and processing time for the file involved makes it impractical to add a formal test case. It has, nevertheless, been tested satisfactorily.

This is:

• a bugfix
• a new feature
• refactoring
• additional unit tests

Checklist:

• Changes are covered by unit tests
  • Changes are covered by existing unit tests
  • New unit tests have been added
• Code style is respected
• Commit message explains why the change is made (see https://github.com/erlang/otp/wiki/Writing-good-commit-messages)
• CHANGELOG.md contains a short summary of the change and a link to the pull request if applicable
• Documentation is updated as necessary