(Review in whitespace changes ignored mode)

failures (6):
    syntax::cdata::lowercase::ns_reader::async_tokio
    syntax::cdata::lowercase::ns_reader::borrowed
    syntax::cdata::lowercase::ns_reader::buffered
    syntax::cdata::lowercase::reader::async_tokio
    syntax::cdata::lowercase::reader::borrowed
    syntax::cdata::lowercase::reader::buffered

… specification

See https://www.w3.org/TR/xml11/#NT-doctypedecl

Start CDATA section only after uppercase `<![CDATA[`

This is not generic code and it is more clear when we construct them with explicit state

If test will fail due to another syntax error we get a nice diff

…er`.

Check position for zero actually does not check anything because this is start
position before parse. We move position by 1 by using Text event

failures (36):
    syntax::tag::unclosed3::ns_reader::async_tokio
    syntax::tag::unclosed3::ns_reader::borrowed
    syntax::tag::unclosed3::ns_reader::buffered
    syntax::tag::unclosed3::reader::async_tokio
    syntax::tag::unclosed3::reader::borrowed
    syntax::tag::unclosed3::reader::buffered
    syntax::tag::unclosed4::ns_reader::async_tokio
    syntax::tag::unclosed4::ns_reader::borrowed
    syntax::tag::unclosed4::ns_reader::buffered
    syntax::tag::unclosed4::reader::async_tokio
    syntax::tag::unclosed4::reader::borrowed
    syntax::tag::unclosed4::reader::buffered
    syntax::tag::unclosed5::ns_reader::async_tokio
    syntax::tag::unclosed5::ns_reader::borrowed
    syntax::tag::unclosed5::ns_reader::buffered
    syntax::tag::unclosed5::reader::async_tokio
    syntax::tag::unclosed5::reader::borrowed
    syntax::tag::unclosed5::reader::buffered
    syntax::tag::unclosed6::ns_reader::async_tokio
    syntax::tag::unclosed6::ns_reader::borrowed
    syntax::tag::unclosed6::ns_reader::buffered
    syntax::tag::unclosed6::reader::async_tokio
    syntax::tag::unclosed6::reader::borrowed
    syntax::tag::unclosed6::reader::buffered
    syntax::tag::unclosed7::ns_reader::async_tokio
    syntax::tag::unclosed7::ns_reader::borrowed
    syntax::tag::unclosed7::ns_reader::buffered
    syntax::tag::unclosed7::reader::async_tokio
    syntax::tag::unclosed7::reader::borrowed
    syntax::tag::unclosed7::reader::buffered
    syntax::tag::unclosed8::ns_reader::async_tokio
    syntax::tag::unclosed8::ns_reader::borrowed
    syntax::tag::unclosed8::ns_reader::buffered
    syntax::tag::unclosed8::reader::async_tokio
    syntax::tag::unclosed8::reader::borrowed
    syntax::tag::unclosed8::reader::buffered

…open or self-closed tag

…here error position is reported

`.error_position()` is intended to report position where error start occurring,
`.buffer_position()` is intended to show to what position reader read data

tests/issues.rs leave untouched because this is the code from real problems in GH issues,
it should remain as close to issue as possible

…e Flash parser)

Allow attributes in the `Event::End` and fix `.error_position()`