Merge pull request #371 from sbesson/homebrew_xquartz

Homebrew xquartz
replacing omero_dir with omero_dist
merge dev_4_4 -D org -I include -E exclude: PR 346 (Training update april 13 1)
merge dev_4_4 -D org -I include -E exclude: PR 361 (Further corrections to troubleshooting)
merge dev_4_4 -D org -I include -E exclude: PR 368 (Cpp: Correct content and markup)