Update README.md (brianc#1247)

grammar fix

Author: ryhamz

README.md

@@ -72,7 +72,7 @@ var config = {
 
 
 //this initializes a connection pool
-//it will keep idle connections open for a 30 seconds
+//it will keep idle connections open for 30 seconds
 //and set a limit of maximum 10 idle clients
 var pool = new pg.Pool(config);