BUG: Whitespace stripping in pep3118 format parser and early free

Closes gh-3348
BUG: Hang on to originally filled Py_Buffer view.

When filling the python buffer view object, python sets
view.shape = &view.len (ndim=1, so this works). If we copy
the view info into our Memoryview object instead of having
it directly filled &view.len points into nirvana.

Closes gh-3175
Merge pull request #4350 from seberg/buffer-fixes

Buffer fixes