resolves #481, #301 encode anchors containing characters outside ASCII range in hex (PR #499)
resolves #481, #301 encode anchors containing characters outside ASCII range in hex (PR #499)

- hex encode anchors that contain characters outside the ASCII range
- squelch the following warning: regexp match /.../n against to UTF-8 string (pdf-core < 0.6.1)
dsisnero/asciidoctor-pdf,asciidoctor/asciidoctor-pdf,dsisnero/asciidoctor-pdf,asciidoctor/asciidoctor-pdf,Hextremist/asciidoctor-pdf,mojavelinux/asciidoctor-pdf,Hextremist/asciidoctor-pdf,mojavelinux/asciidoctor-pdf