Updated Introduction (markdown)

Introduction.md

@@ -5,9 +5,11 @@ There are two types of expressions in Biosphere2:
 The usual workflow is that you first create a bunch of locations or vectors. In a second step you apply some transformation to them. And in a final step you do something with them. This is best shown by an example:
 ```
 # 1) creation step (create locations in the shape of a circle)
-set {_circle::*} to circle at player with radius 1 and density 5 
+set {_circle::*} to circle at player with radius 1 and density 5
+
 # 2) transformation step (make circle 2 times larger)
-set {_bigcircle::*} to {_circle::*} scaled at player by 2 
+set {_bigcircle::*} to {_circle::*} scaled at player by 2
+
 # 3) do something with your locations (not part of Biosphere2)
 show happy villager at {_bigcircle::*} 
 ```