8076543: Add @modules as needed to the langtools tests
Reviewed-by: jjg, shurailine

8038730: Clean up the way JavadocTester is invoked, and checks for errors.
Reviewed-by: ksrini, sogoel, bpatel

8040904: Ensure javadoc tests do not overwrite results within tests
Reviewed-by: ksrini

8040903: Clean up use of BUG_ID in javadoc tests
Reviewed-by: ksrini

8041150: Avoid silly use of static methods in JavadocTester
Reviewed-by: ksrini

8031649: Clean up javadoc tests
Reviewed-by: jjg
Contributed-by: neil.toda@oracle.com

8024288: javadoc generated-by comment should always be present
Reviewed-by: bpatel

8000418: javadoc should used a standard "generated by javadoc" string
Reviewed-by: bpatel