Consider using python-libzim instead of zimply-core

[libzim](https://github.com/openzim/libzim) is the official implementation of the ZIM specification. It has [Python bindings](https://github.com/openzim/python-libzim) and is more tested and maintained than ZIMply/ZIMply-core.

One issue though is that [no binaries are provided](https://github.com/openzim/python-libzim/issues/91) for libzim at the moment, so we have to compile it ourselves. I've not been successful so far and this was my prime reason for choosing ZIMply, but the latter has its issues: https://github.com/abdnh/anki-zim-reader/issues/3

Start by reviewing the current ZIMply/ZIMply-core integration and the linked python-libzim project, especially python-libzim issue 91 about missing binaries. Determine whether the bindings can be compiled and integrated reliably; done means the add-on can use the maintained library without regressing ZIM viewing or extraction.

Escrita pelo modelo de indexação a partir do texto da issue.