Merge remote-tracking branch 'upstream/master'

MEMO

doc/reference.rst

loopy/__init__.py

loopy/array_buffer_map.py

loopy/auto_test.py

loopy/buffer.py

loopy/diagnostic.py

loopy/isl_helpers.py

loopy/kernel/__init__.py

loopy/kernel/array.py

loopy/kernel/creation.py

loopy/kernel/data.py

loopy/padding.py

loopy/precompute.py

loopy/preprocess.py

loopy/subst.py

loopy/symbolic.py

loopy/tools.py

test/test_fortran.py

test/test_linalg.py