Hunk edits to isolate the new function interface

doc/index.rst

loopy/__init__.py

loopy/check.py

loopy/codegen/__init__.py

loopy/kernel/__init__.py

loopy/kernel/creation.py

loopy/kernel/tools.py

loopy/library/function.py

loopy/library/random123.py

loopy/library/reduction.py

loopy/preprocess.py

loopy/statistics.py

loopy/symbolic.py

loopy/target/__init__.py

loopy/target/c/__init__.py

loopy/target/c/codegen/expression.py

loopy/target/cuda.py

loopy/target/opencl.py

loopy/target/pyopencl.py

loopy/target/python.py