[DRE-maint] Bug#893467: split asciidoctor into ruby-asciidoctor

[Helmut Grohne]

Package: asciidoctor
Version: 1.5.5-1
User: helmutg at debian.org
Usertags: rebootstrap
Control: affects -1 + src:icewm

icewm Build-Depends on asciidoctor and that dependency is cross
unsatisfiable, because asciidoctor is Architecture: all and implicitly
Multi-Arch: no. It would have to be marked Multi-Arch: foreign to
satisfy the dependency, but asciidoctor happens to also ship the
asciidoctor ruby module. Thus, such a marking would be wrong. Please
separate the asciidoctor library from the asciidoctor program in the
packaging creating a ruby-asciidoctor package. Alternatively, if the
asciidoctor module is not meant to be used by others, move it to a
private path. After doing so, we can likely mark the asciidoctor program
(but not the library) Multi-Arch: foreign and thus help icewm.

Helmut