Update ReadMe.md

ReadMe.md

@@ -14,6 +14,16 @@ This will now convert the contents of the wikipedia_misspell.txt into Primo miss
 
 Copy the newly prioducted $version/misspell_eng.txt to the Primo misspelling directory at ng/jaguar/home/profile/analysis/misspelling/
 
+### Why 
+
+Primo comes with only 130 misspellings, by merging in the Wikipedia source this brings it to over 4,000
+and by combining your own misspellings file you can customise this as much as you want
+
+Here is a screenshot of it in action
+{http://i.minus.com/ibf7h8VFi2cDkM.png}
+
+The yotube=>youtube comes from the wikipedia list, this is anexample of a usefull misspelling that ExLibris are unlikely to include
+
 ### Extending
 
 If you want to create a misspellings file for a version of Primo not listed just create a subfolder with the version number ie 3.1.0,