Reactivate building of lapack_lite

- numpy/linalg/lapack_lite.py: Delete placeholder file.
- numpy/distutils/misc_util.py: Add 'activate' flag to selectively
  activate building of a module. Use in numpy/linalg/setup.py.
  Note that numpy/core/include must be renamed so that the PyPy
  headers are found.
- numpy/core/multiarray.py: Add implemenations for copyto() and
  fastCopyAndTranspose().
- numpy/core/numeric.py: ones(): Use numpypy's implementation.