added feature list

README.md

@@ -7,6 +7,20 @@
 
 # A minimal Python package that plots slices of OpenMC regular mesh tallies with the model geometry.
 
+Features
+
+:straight_ruler: Axis units in in helpful units mm, cm, m, km
+
+:eyes: Supports all 3 viewing basis (xy, xz, yz)
+
+:hocho: Automaticly finds central slice or allows user specified slice index
+
+:dart: Supports all values (mean, std_dev etc)
+
+:black_square_button: Adds outlines for geometry cells or material at different pixel resolution
+
+:arrow_right_hook: Customisable by passing keywords to underlying matplotlib functions colorbar, contour and imshow
+
 |<img src="https://user-images.githubusercontent.com/8583900/265032335-27463ee9-8960-4f5e-a662-dab0b6cd9fc5.png" alt="drawing" width="400"/>|<img src="https://user-images.githubusercontent.com/8583900/265065370-734c66ab-b20e-40c8-b72b-88203ea4347b.gif" alt="drawing" width="400"/>|
 
 # Local install