Fix link to 2FA on help.github.com
Changing page order
Fix description of submodule PRs inclusion using scc merge commands
Add note about scc travis-merge limitation
Fix as per @mtbc's suggestion
Use http rather than https links for Sphinx linkchecker
Improve description of file annotation utility functions
Use verbatim for references to Pixels/Image object
merge develop -D org -I include -E exclude: PR 533 (Removing BF anchor until it exists)
merge develop -D org -I include -E exclude: PR 557 (remind that model changes may affect IceMapper)
merge develop -D org -I include -E exclude: PR 565 (Add paragraph about GitHub 2FA and scc commands)
merge develop -D org -I include -E exclude: PR 566 (Document latest OMERO.matlab functions)
merge develop -D org -I include -E exclude: PR 567 (Updating contributing developer guidance)
merge develop -D org -I include -E exclude: PR 568 (Submodule dependency fix)