Break at 80 in README.

README

@@ -7,10 +7,11 @@ This version is known to compile with:
  - Ssreflect 1.6
  - Autosubst 1.4
 
-For development, better make sure you have a version of Ssreflect that includes commit be724937
-(no such version has been released so far, you'll have to fetch the development branch yourself).
-Iris compiles fine even without this patch, but proof bullets will only be in 'strict' (enforcing)
-mode with the fixed version of Ssreflect.
+For development, better make sure you have a version of Ssreflect that includes
+commit be724937 (no such version has been released so far, you will have to
+fetch the development branch yourself). Iris compiles fine even without this
+patch, but proof bullets will only be in 'strict' (enforcing) mode with the
+fixed version of Ssreflect.
  
 BUILDING INSTRUCTIONS
 ---------------------