clarify memoryview example in userguide
make sure memoryview example actually runs (fix typing errors)
more clarification on memoryview example (indexing syntax)
memoryviews example: use native ints, no more libc.stdint
Add test for memoryview of extension type

A test for a bug fixed in commit 478b939a4c99a77c0863cfd.

v2: add commit link above
v3: # tag: instead of # tags:, drop cpp tag as it means something different
    that I originally thought

There was a bug that produced C code where gcc emitted warnings:
extension_type_memoryview.c: In function ‘__pyx_pf_25extension_type_memoryview_test_getitem’:
extension_type_memoryview.c:1468:15: warning: assignment from incompatible pointer type
extension_type_memoryview.c: In function ‘__pyx_pf_25extension_type_memoryview_2test_getitem_typed’:
extension_type_memoryview.c:1565:15: warning: assignment from incompatible pointer type
extension_type_memoryview.c:1568:18: warning: assignment from incompatible pointer type

And g++ failed with errors:
extension_type_memoryview.c: In function ‘PyObject* __pyx_pf_25extension_type_memoryview_test_getitem(PyObject*)’:
extension_type_memoryview.c:1468:213: error: cannot convert ‘__pyx_obj_25extension_type_memoryview_ExtensionType*’ to ‘PyObject*’ in assignment
extension_type_memoryview.c: In function ‘PyObject* __pyx_pf_25extension_type_memoryview_2test_getitem_typed(PyObject*)’:
extension_type_memoryview.c:1565:213: error: cannot convert ‘__pyx_obj_25extension_type_memoryview_ExtensionType*’ to ‘PyObject*’ in assignment
extension_type_memoryview.c:1568:20: error: cannot convert ‘PyObject*’ to ‘__pyx_obj_25extension_type_memoryview_ExtensionType*’ in assignment

--HG--
extra : transplant_source : %02N%D4%B99N%D6%FBv%7C%F0%94%E5%BE%CE%C9t%D6%04%11
drop 'vile hack' by restricting state changes of AttributeNode during infer_type() to what analyse_types() does
make sure utility code loaded for header files and module preamble gets properly formatted
fix test
add .py test for 'binding' effect

--HG--
rename : tests/run/function_as_method_T494.pyx => tests/run/function_as_method_py_T494.py
disable checks in test that are unrelated to the tested behaviour
add comment in test
enable working tests from bugs.txt
prevent special __weakref__ attribute from triggering generation of garbage collection code for the type
Py3 test fixes
fix version extraction in Sphinx build
include PDF-Builder in Sphinx conf (if installed)
add PDF doc building target
Cast extension types in memoryviews for C++ code
update Sphinx docs config
merge