Merge pull request #639 from sbesson/rebased/develop/homebrew_4410

Document latest changes to the Homebrew OMERO formula (rebased onto develop)
Updating Till Photonics website link
Merge pull request #643 from hflynn/till-photonics

Updating Till Photonics website link
Add --devel option to install the OMERO 5 via Homebrew
merge develop -D org -I include -E exclude: PR 626 (Add new Squash tutorial and screenshots)
merge develop -D org -I include -E exclude: PR 645 (Add --devel option to install the OMERO 5 via Homebrew (rebased onto develop))