519262: create target for Eclipse Photon (4.8)

We are not updating to the latest Orbit because the only dependency with
a new qualifier is HTTP Client, and Photon is not using that version per
https://dev.eclipse.org/mhonarc/lists/cross-project-issues-dev/msg15659.html

Change-Id: I9b520946002b7f802c0c3b4b0de7093ceb1f2aa7
Task-Url: https://bugs.eclipse.org/bugs/show_bug.cgi?id=519262
3 files changed