Expanded explanation of Defaults button in Namespaces tab of Configure Compilers dialogue.

Also fixed some typos.

Author: DelphiDabbler

Src/Help/HTML/dlg_configcompilers.htm

@@ -4,7 +4,7 @@
  * v. 2.0. If a copy of the MPL was not distributed with this file, You can
  * obtain one at http://mozilla.org/MPL/2.0/
  *
- * Copyright (C) 2005-2015, Peter Johnson (www.delphidabbler.com).
+ * Copyright (C) 2005-2016, Peter Johnson (www.delphidabbler.com).
  *
  * $Rev$
  * $Date$
@@ -193,11 +193,14 @@ <h2>
         This can be useful if you have made some changes to namespaces and
         <em>CodeSnip</em> fails to compile snippets correctly. The default
         namespaces have been chosen because they contain the most commonly used
-        units.
+        units. <strong>Note:</strong> New releases of <em>CodeSnip</em> may
+        change the default namespaces. Should this happen after you have
+        customised the namespaces you will need to use the <em>Defaults</em>
+        button to force the program to recognise the new default settings.
       </li>
     </ul>
     <p>
-      For an list of RTL and VCL units, and the namespaces to which thet belong,
+      For a list of RTL and VCL units, and the namespaces to which they belong,
       see your compiler's documentation.
     </p>
     <h2>