#37 alert for browser incompatibility

sails/src/assets/scripts/check_browser.js

@@ -17,7 +17,10 @@ var clientBrowser = (function(){
 
 // Return if client browser valid or not
 var validBrowser = false;
-if(clientBrowser[0] == "Firefox" && parseInt(clientBrowser[1]) >= 52 )
+
+if(clientBrowser[0] == "Firefox" && parseInt(clientBrowser[1]) >= 51 )
   validBrowser = true;
 if(clientBrowser[0] == "Chrome" && parseInt(clientBrowser[1]) >= 51 )
   validBrowser = true;
+
+if(!validBrowser) alert("Su navegador no es compatible con Pictogram Web. Actualice a la última versión de Mozilla Firefox o Google Chrome.");