====== newShape ======

  * Parameters & Types:
     * type: number tag
     * isshow: whether the boolean is displayed
      * r,g,b:number color value (range 0~255)
  * Return value and type:
     * ErrorCode. OK
     * shapeid:number
  * The main purpose of this method: to add a new shape (line, rectangle, circle)
  * Specific use cases are as follows:
<code>
-- Create a black line on the map and display it (doesn't seem to have any effect)
--The first parameter 0 is the shape type: 0 line, 1 rectangle, 2 round
--The second parameter is whether it is displayed: true yes false no
--The last three parameters are the shape color, which are R, G, B (red, green, blue)
local result,shapeid=MapMark:newShape(0,true,0,0,0)
-- Show in chat box
Chat:sendSystemMsg("A black line was created!")
</code>