typo

README.md

@@ -19,7 +19,7 @@ For the impatient:
     go get github.com/irifrance/gini...
 
 I recommend however building the package github.com/irifrance/gini/internal/xo with bounds checking
-turned off.  This package is all about anything-goes performance and is the workhorse behing most of
+turned off.  This package is all about anything-goes performance and is the workhorse behind most of
 the gini sat solver.  It is also extensively tested and well benchmarked, so it should not pose any
 safety threat to client code.  This makes a signficant speed difference (maybe 10%) on long running
 problems.