Merge pull request #276 from kmike/fix-strings-tutorial

fix deprecated imports in "Unicode and passing strings" tutorial
remove reference to unused utility code
use an actual set() for Scope.types_imported instead of a set-ishly used dict
use arbitrary but predictable C code order when cleaning up imported extension types
uncomment vector assign function template
Merge pull request #277 from Hinogary/master

some minor changes
minor doc improvement
save a malloc() call when instantiating cython.array()

--HG--
extra : amend_source : 8ea50b285fc8d55899450c179754d7c2aba94591
reduce overhead for cython.array() initialiser a bit
fix memory leak in exception case
use CPython heap memory allocation for memory views where possible (outside of nogil sections) as it tends to be faster than plain malloc()
whitespace fix
fix format checking for cython.array.__getbuffer__() in Py3

--HG--
extra : amend_source : 685e555a2102e496280287b3b7605d67d694ff40
add fixme comment
simplify shape unpacking code in cython.array initialiser

--HG--
extra : amend_source : 4d5d9dc96421710652afe8614c9f32db26cc88c1
make it easier for the C compiler to prune some useless error checking code in cython.array constructor
revert to using malloc/free for data buffer allocation in case external code wants to fiddle with it
fix memory leak in memory views when copying overlapping contiguous slices

--HG--
extra : amend_source : 6c9be6e15396919e08090d9d12557c4255fd8a3c
fix crash by excluding heap types from the extension type freelists
apply freelist type check also when *adding* dead objects to the freelist to make sure their eventual cleanup works correctly