Compute each Makefile variable immediately

Otherwise the variables get re-computed over and over again every time
they are used, slowing things up.  Especially if someone adapts the
Makefile to several targets in their own real project. :)

revert to using codecs.open() for output files instead of io.open() as the latter cannot write str objects in text mode under Py2 (and we erroneously do that in some spots)

make encoding detection code a bit faster if the first two source file lines are longer than 250 bytes

Get rid of obsolete Python cruft.

cython-mode.el: don't highlight builtins when they're part of varname

simplify test for GCC >= 2.95 for branch prediction

document memoryview attributes better

--HG--
extra : amend_source : 9ae2e52935ae16af23c35b6329d53e559b7c39d0

Fixed typo

(I know, I know. It was just too visible.)

To avoid mismatches keywords should be checked at symbol, not word
boundaries, otherwise they'll ignore underscores (is_*float*).

apply freelist type check also when *adding* dead objects to the freelist to make sure their eventual cleanup works correctly