code: def addEnvPath(env, name, value):
      
      try:
          oldval = env[name]
          if not oldval.endswith(';'):
              oldval = oldval + ';'
      except KeyError:
          oldval = ""
      if not value.endswith(';'):
          value = value + ';'
      env[name] = oldval + value
docs: concat a path for this name