Update the README description

Author: wawong

README.md

@@ -1,4 +1,9 @@
 # CIL_Image_Viewer
-This image viewer utilizes the Leaflet library and the CodeIgniter PHP library for browsing the high definition images.
 
-![CIL Image Viewer](https://spirilli.crbs.ucsd.edu/images/cil_image_viewer_demo.JPG)
+![CIL Image Viewer](https://spirilli.crbs.ucsd.edu/images/cil_image_viewer_demo.JPG)
+
+This image viewer utilizes the Leaflet library and the CodeIgniter PHP library for browsing the high definition images.
+This image viewer is capable of displaying confocal images, electron tomography z-stack images, and time-series images. 
+This user-interface includes image controls such as zooming, panning, contrast adjustment, brightness adjustment, moving 
+Z-stack location, moving the time location and the annotation drawing capabilities. Each of these events will trigger 
+the web-service call in Javascript to fetch the latest data.