Add example to test the Python module being renamed to __init__.py

This examples tests the SWIG generated module being placed into a directory and
then renamed __init__.py to convert the module into a package. This ability
stopped working in swig-3.0.9. However, only Python 2.7 or 3.3 and later work. If
Python 3.2 support is needed, use moduleimport in %module to customise the import
code.

Issue #1282

Examples/python/import_packages/module_is_init/pkg1/Makefile

@@ -0,0 +1,20 @@
+TOP        = ../../../..
+SWIGEXE    = $(TOP)/../swig
+SWIG_LIB_DIR = $(TOP)/../$(TOP_BUILDDIR_TO_TOP_SRCDIR)Lib
+SWIGOPT    =
+LIBS       =
+
+build:
+	$(MAKE) -f $(TOP)/Makefile SRCDIR='$(SRCDIR)' \
+	SWIG_LIB_DIR='$(SWIG_LIB_DIR)' SWIGEXE='$(SWIGEXE)' \
+	SWIGOPT='$(SWIGOPT)' LIBS='$(LIBS)' TARGET='foo' INTERFACE='foo.i' python_cpp
+	mv foo.py __init__.py
+
+static:
+	$(MAKE) -f $(TOP)/Makefile SRCDIR='$(SRCDIR)' \
+	SWIG_LIB_DIR='$(SWIG_LIB_DIR)' SWIGEXE='$(SWIGEXE)' \
+	SWIGOPT='$(SWIGOPT)' LIBS='$(LIBS)' TARGET='foo' INTERFACE='foo.i' python_cpp_static
+
+clean:
+	$(MAKE) -f $(TOP)/Makefile SRCDIR='$(SRCDIR)' TARGET='foo' python_clean
+	rm -f __init__.py

Examples/python/import_packages/module_is_init/pkg1/foo.hpp

@@ -0,0 +1,10 @@
+
+int foofunction(int i) {
+  return i *= 10;
+}
+
+struct FooClass {
+  int foomethod(int i) {
+    return i += 5;
+  }
+};

Examples/python/import_packages/module_is_init/pkg1/foo.i

@@ -0,0 +1,5 @@
+%module foo
+%{
+#include "./foo.hpp"
+%}
+%include "./foo.hpp"