title: Draw a horizontal line, scaling of axis and time as scale using achartengine in android
body: <p>I'm using AchartEngine library to draw the line graph for the output received from a external device as part of our project in Android. 
  1. How to draw a horizontal line using AchartEngine at a constant value throughout the graph.
  2. How to set scale for x-axis,y-axis of graph. ex., Let y-axis starts with 0,ends at 1100.. there will be scale for each 100 but i need to start with 50 at the same time that 50 should appear at the place of 100(but not just in between 0 to 100), 100 should appear at the point of 200 and 150 should appear at the position of 300. (I had already set the min.axis,max.axis)
  3. How to set the current time at the x-axis as scale? ie., instead of number(1,2,3...) as scale there is need of time as x-axis scale which can system time.</p>