Implement "from module import *" construct.
Add testcase for "from module import sym".
Add testcase for "from module import *".
stm: If SD card inserted on hard reset, it is the medium for USB MSD.
Allow ports to define statically builtin functions.

Convert unix open() to such.
ffi: Implement ffivar.get()/set() methods.

Done by introducing another factored out helper API in binary.c. This API
can be reused also by array and struct modules.
objarray: Refactor to use array accessors from binary.c .
objexcept: Fix a case of initialized object field.
mp_binary_get_val(): Fix value type.
OS X compatible -map syntax for LDFLAGS
Merge pull request #282 from pfalcon/from-star

Implement "from mod import *"
Merge pull request #288 from pfalcon/port-builtins

Allow ports to define statically builtin functions.
py: Fix IMPORT_STAR, needs to pop the stack.
Merge pull request #291 from GordonMcGregor/osx_build

OS X compatible -map syntax for LDFLAGS
Add testcase for failing namespace switch throwing exception from a module.

Issue #290. This currently fails, to draw attention to the issue.
Change mp_obj_type_t.name from const char * to qstr.

Ultimately all static strings should be qstr.  This entry in the type
structure is only used for printing error messages (to tell the type of
the bad argument), and printing objects that don't supply a .print method.
Implement proper exception type hierarchy.

Each built-in exception is now a type, with base type BaseException.
C exceptions are created by passing a pointer to the exception type to
make an instance of.  When raising an exception from the VM, an
instance is created automatically if an exception type is raised (as
opposed to an exception instance).

Exception matching (RT_BINARY_OP_EXCEPTION_MATCH) is now proper.

Handling of parse error changed to match new exceptions.

mp_const_type renamed to mp_type_type for consistency.
py: Pass all scope flags through to runtime.
py: Improve exception bases, reduces ROM usage.

Thanks to @pfalcon for the tip!
Small change to configuration of long int.