adding in nature example

Author: Ian Eyberg

nature/README.md

@@ -0,0 +1,15 @@
+Compile:
+
+```
+nature build main.n
+```
+
+Run:
+
+```
+eyberg@s1:~/n$ ops run main
+running local instance
+booting /home/eyberg/.ops/images/main ...
+en1: assigned 10.0.2.15
+hello world
+```

nature/main.n

@@ -0,0 +1 @@
+print('hello world')