Clean up httpcomponents-client

- 4.2.1 appears to be missing on the mirrors so it's bumped to 4.2.3.
- Add a workaround for bundled httpcore-4.2.2
- Change SRC_URI to use mirror://apache
- An empty metadata.xml is added to make repoman happy

Package-Manager: portage-2.1.11.52
Add a dependency on otopi

Package-Manager: portage-2.1.11.52