constructive 1.3.0

1.2.0 couldn't be installed on some OS, R versions, or combinations of the latter, this is addressed in 1.3.0 along with a few additional fixes and features so it ends up being a new minor version.

• We construct external pointers differently, from a global store in the package's namespace rather than from an address. It's more accurate and the previous way seemed to be problematic on Windows. xml2::read_html
• matrix() and array() are not used anymore when calling construct_dput(), this is consistent with dput().
• A new "prototype" constructor for objects of class "S4" allows faithful construction of S4 objects that have an initialize() method
• We construct object of the "xml_document" class using xml2::read_html() or xml2::read_xml()
• .cstr_new_class() and .cstr_new_constructor() work with VSCode and VSCode based editors.
• We're a bit more careful when using recycling on data frame columns. Previously we were not accurate when recycled columns had some attributes.