Do a git push, too

Rakefile

@@ -21,10 +21,13 @@ task :serve do
 end
 
 task :upload => :build do
-  current_branch = `git branch 2>/dev/null | awk '/^\* /{print $2}'`
-  sh "git checkout gh-pages"
-  sh "cp -R .html/.* ."
-  sh "git add ."
-  sh "git commit -m 'P U B L I S H'"
-  sh "git checkout #{current_branch}"
+  current_branch = `git branch 2>/dev/null | awk '/^\* /{print $2}'`.strip
+  ["git checkout gh-pages",
+   "rsync -rv .html/.* .",
+   "git add .",
+   "[[ -z `git status --porcelain` ]] || (git commit -m 'P U B L I S H' ; git push -f)",
+   "git checkout #{current_branch}"].all? do |cmd|
+                                     # We use all? so that we'll abort if anything fails.
+     sh cmd, verbose: true
+   end
 end