AsciidoctorJ 1.6 is not backwards compatible with AsciidoctorJ 1.5
and AsciidoctorJ 2.0 is not backwards compatible with AsciidoctorJ 1.6
or 1.5. The backwards incompatibilities are such that they cannot be
worked around using reflection so code needs to be compiled against
each of the three versions. To this end, this commit splits
spring-restdocs-asciidoctor into several separate modules:
1. spring-restdocs-asciidoctor-support
2. spring-restdocs-asciidoctor-1.5
3. spring-restdocs-asciidoctor-1.6
4. spring-restdocs-asciidoctor-2.0
spring-restdocs-asciidoctor-support contains support code that is not
tied to a specific version of AsciidoctorJ and can be used with
1.5, 1.6 and 2.0. The other three modules contain code that is
specific to a particular version of AsciidoctorJ. Each
version-specific module uses class names that are unique across all
three modules and is written in such a way that they will back off
when used in an environment with a different version of AsciidoctorJ.
The existing spring-restdocs-asciidoctor module has been modified to
merge the version specific jars and the support jar together into a
single jar that supports AsciidoctorJ 1.5, 1.6, and 2.0.
The above-described changes should allow users to depend upon
spring-restdocs-asciidoctor as before and to now be able to use
AsciidoctorJ 1.5, 1.6, or 2.0.
Closes gh-581
