small README markup change
small README markup change

Related issue #41

joshua317/nanoScrollerJS,juriejan/nanoScrollerJS,jomko/nanoScrollerJS,hagiang1305/nanoScrollerJS,Invulner/nanoScrollerJS,jamesflorentino/nanoScrollerJS,hagiang1305/nanoScrollerJS,modulexcite/nanoScrollerJS,jamesflorentino/nanoScrollerJS,minhliem86/nanoScrollerJS,juriejan/nanoScrollerJS,widgetic/nanoScrollerJS,minhliem86/nanoScrollerJS,jomko/nanoScrollerJS,SimilarWeb/nanoScrollerJS,modulexcite/nanoScrollerJS,SimilarWeb/nanoScrollerJS,joshua317/nanoScrollerJS,widgetic/nanoScrollerJS,Invulner/nanoScrollerJS