Changes

WIP to support Jetty 9 and 10

- Move org.eclipse.userstorage.tests from using Require-Bundle to
  import-package
- Remove use of deprecated Jetty logger; tests show Jetty output,
  but that is actually useful
- Fix uses of sendError() to setStatus() to preserve response headers
- Wire to org.apache.httpcomponents.httpclient < 4.5.0

- added new .target for eclipse-latest, orbit-latest, and jetty 10
  for configuring Eclipse
- added new profiles to build and test for other named Eclipse releases

    mvn -Declipse.target=neon verify

  or use the following to test with Jetty 10

    mvn -Declipse.target=latest verify

Change-Id: I385b9c883bc4615e372a08238a2a158010368825
Signed-off-by: Brian de Alwis <bsd@acm.org>