Add simple branch name gen for sh and ps1

vendor/git-prompt.sh

@@ -9,6 +9,21 @@ function getGitStatusSetting() {
   fi
 }
 
+function getSimpleGitBranch() {
+  gitDir=$(git rev-parse --git-dir 2>/dev/null)
+  if [ -z "$gitDir" ]; then
+		return 0
+	fi
+  
+  headContent=$(< "$gitDir/HEAD")
+  if [[ "$headContent" == "ref: refs/heads/"* ]]
+  then
+      echo " (${headContent:16})"
+  else
+      echo " (HEAD detached at ${headContent:0:7})"
+  fi 
+}
+
 if test -f /etc/profile.d/git-sdk.sh
 then
   TITLEPREFIX=SDK-${MSYSTEM#MINGW}
@@ -45,6 +60,9 @@ else
         . "$COMPLETION_PATH/git-prompt.sh"
         PS1="$PS1"'\[\033[36m\]'  # change color to cyan
         PS1="$PS1"'`__git_ps1`'   # bash function
+      else
+        PS1="$PS1"'\[\033[30;1m\]'  # change color to gray
+        PS1="$PS1"'`getSimpleGitBranch`'
       fi
     fi
   fi