Added support for a commit message suffix
Added support for a commit message suffix

Using the COMMIT_MESSAGE_SUFFIX env var

auscaster/middleman-gh-pages,jagthedrummer/middleman-gh-pages,hugomaiavieira/middleman-gh-pages,patilswapnilv/middleman-gh-pages,baroquebobcat/middleman-gh-pages,heirloompixels/middleman-gh-pages,neo/middleman-gh-pages,cybernetlab/middleman-gh-pages,rmm5t/middleman-gh-pages,ashfurrow/middleman-gh-pages,mattlima/middleman-gh-pages,orta/middleman-gh-pages,edgecase/middleman-gh-pages