Generate API Documentation in AsciiDoc Format Using OpenAPI Generator

Thanks "man-at-home" (https://github.com/man-at-home) for contributing an AsciiDoc documentation generator to [OpenAPI Generator](https://github.com/OpenAPITools/openapi-generator). To generate API documentation in AsciiDoc format, please follow 3 simple steps below:

1. Download the Java JAR (https://oss.sonatype.org/content/repositories/snapshots/org/openapitools/openapi-generator-cli/4.1.3-SNAPSHOT/openapi-generator-cli-4.1.3-20190920.093941-26.jar)

2. Rename the JAR as "openapi-generator-cli.jar"

3. Run the following command to generate API documentation in AsciiDoc format for the Petstore API (https://raw.githubusercontent.com/OpenAPITools/openapi-generator/master/modules/openapi-generator/src/test/resources/2_0/petstore.yaml):

Mac/Linux:

- java -jar openapi-generator-cli.jar generate -g asciidoc -i https://raw.githubusercontent.com/OpenAPITools/openapi-generator/master/modules/openapi-generator/src/test/resources/2_0/petstore.yaml -o /var/tmp/asciidoc/

Windows:

- java -jar openapi-generator-cli.jar generate -g asciidoc -i https://raw.githubusercontent.com/OpenAPITools/openapi-generator/master/modules/openapi-generator/src/test/resources/2_0/petstore.yaml -o C:\tmp\asciidoc

If you've any feedback or question, please let us know via https://github.com/OpenAPITools/openapi-generator/issues/new