Fix minor typos in certs/warning.txt

Author: forevermatt

onelogin-saml-sso/php/certs/warning.txt

@@ -2,9 +2,9 @@ This 'certs' folder must never be published.
 
 Alternatives:
 
-1. Using the .htaccess if the AllowOveride at your Apache Server is active
+1. Using the .htaccess if the AllowOverride at your Apache Server is active
 
-2. Add a Directoy at your Apache server:
+2. Add a Directory at your Apache server:
 
 <Directory /<path-to-onelogin-saml-sso-plugin>/php/certs
     Order deny,allow