Merge branch 'stable-2.12'
* stable-2.12:
Add a test for Asciidoctor document titles / sections
Add correct license for asciidoctor
Make the basicTextFormattingWorks() test more strict
Add tests to check that empty input renders to empty output
AsciidoctorFormatterTest: Fix order of expected and actual results
AsciidoctorFormatterTest: Do not pass baseDir to AsciidoctorFormatter()
AsciidoctorFormatter: Simplify code by using the Asciidoctor >= 1.5 API
Upgrade asciidoctor and its jruby dependency
Add a unit test for the AsciidoctorFormatter
Upgrade asciidoctor and its jruby dependency
MarkdownFormatterTest: Fix order of expected and actual results
MarkdownFormatterTest: Make a few member variables local ones
xdocs: Add a unit test for the MarkdownFormatter
Change-Id: I99578f15906a3fa7a75d9ea500d502f1948b8720