Updated git aliases

+ changed gs to git status
+ made gss git stash save
+ added gd for git diff

git/git.zsh

@@ -4,8 +4,9 @@ alias ga='git add'
 alias gb='git branch'
 alias gl='git pull'
 alias gp='git push'
-alias gst='git s'
-alias gs='git stash save'
+alias gd='git diff'
+alias gs='git s'
+alias gss='git stash save'
 alias gsp='git stash pop'
 alias gmv='git mv'
 alias grm='git rm'