Merge pull request #329 from juanghurtado/master

Support for $(current_branch) on git_parse_ahead()

lib/git.zsh

@@ -15,7 +15,7 @@ parse_git_dirty() {
 
 # Checks if there are commits ahead from remote
 function git_prompt_ahead() {
-  if $(echo "$(git log origin/master..HEAD 2> /dev/null)" | grep '^commit' &> /dev/null); then
+  if $(echo "$(git log origin/$(current_branch)..HEAD 2> /dev/null)" | grep '^commit' &> /dev/null); then
     echo "$ZSH_THEME_GIT_PROMPT_AHEAD"
   fi
 }