py/mpconfig.h: Introduce MICROPY_PY_NATIVE_TYPE_INIT_METHODS.
py/mpconfig.h: Introduce MICROPY_PY_NATIVE_TYPE_INIT_METHODS.

Intended to control availability of __init__ methods for native types
(list, dict, etc.). Enabled by default, because code size impact if fairly
modest (128 bytes x86 32-bit), and allows existing tests to work (and
otherwise skipping them is fairly problematic given that __init__ is
inherited from object if not defined in the type itself (so, checking
whether a particular type defines __init__ itself would require access
to __dict__, and that's what we'd like to avoid as an implementation
detail)).

The methods themselves will be added later.

Change-Id: I7716ff64a207dba7fbe3bd84375bd045ecea6876
Signed-off-by: Paul Sokolovsky <9dc5061f178bb11813e14f1ed02ba27eaf21fa5d@users.sourceforge.net>

pfalcon/micropython,pfalcon/micropython,pfalcon/micropython,pfalcon/micropython,pfalcon/micropython