[cmake] Fix broken tests after change in TRIQS install macros

- After the change in main lib, need to put explicitely the
  sitecustomize file

cmake/sitecustomize.py

@@ -0,0 +1,8 @@
+def application_pytriqs_import(name,*args,**kwargs):
+  if name.startswith('@package_name@'):
+    name = name[len('@package_name@')+1:]
+  return builtin_import(name,*args,**kwargs)
+
+import __builtin__
+__builtin__.__import__, builtin_import = application_pytriqs_import, __builtin__.__import__
+

python/CMakeLists.txt

@@ -1,5 +1,9 @@
 # where will the python end up in triqs?
 set(python_destination applications/dft)
 
+# site_customize for build
+set(package_name "pytriqs.applications")
+configure_file(${CMAKE_SOURCE_DIR}/cmake/sitecustomize.py ${CMAKE_CURRENT_BINARY_DIR}/sitecustomize.py @ONLY)
+
 # make a local pytriqs copy
 triqs_prepare_local_pytriqs(${python_destination})