hg: jdk/sandbox: 8227170: (.hg)Ignore the JTwork and JTreport directories generated at the root of the repo

[chris.hegarty at oracle.com]

Changeset: 0d17da18142b
Author:    jpai
Date:      2019-07-29 16:31 +0530
URL:       https://hg.openjdk.java.net/jdk/sandbox/rev/0d17da18142b

8227170: (.hg)Ignore the JTwork and JTreport directories generated at the root of the repo
Summary: Fix the .hgignore file to properly ignore the following: .DS_Store file, .metadata, .recommenders, JTwork and JTreport directories at the root of the repo (in addition to being ignored as sub-directories). src/utils/hsdis/build/ directory
Reviewed-by: erikj

! .hgignore