Document the module attribute in %import and add warning to Python for when it should be used

git-svn-id: https://swig.svn.sourceforge.net/svnroot/swig/trunk@10866 626c5289-ae23-0410-ae9c-e8d60b6d4f22

Examples/test-suite/import_nomodule.i

@@ -3,6 +3,9 @@
 #include "import_nomodule.h"
 %}
 
+// For Python
+%warnfilter(SWIGWARN_TYPE_UNDEFINED_CLASS) Bar; // Base class 'Foo' ignored - unknown module name for base. Either import the appropriate module interface file or specify the name of the module in the %import directive. 
+
 %import "import_nomodule.h"
 
 #if !defined(SWIGJAVA) && !defined(SWIGRUBY) && !defined(SWIGCSHARP)

Examples/test-suite/imports_b.i

@@ -34,9 +34,14 @@
 */
 
 #if 0
-%import "imports_a.i"
+  %import "imports_a.i"
 #else
-%import(module="imports_a") "imports_a.h" 
+#  if 0
+  // Test Warning 401 (Python only)
+  %import "imports_a.h" 
+#  else
+  %import(module="imports_a") "imports_a.h" 
+#  endif
 #endif
 
 %include "imports_b.h"