MAINT: Improve computation of scaled companion matrices.

The previous method used for hermite and hermite_e polynomials suffered
from double overflow for polynomials of large degree. Those numbers were
later scaled down by equally large numbers, but the result was NaN. The
wanted values are now computed in such a way that overflow in some
entries is replaced by underflow in others. The resulting zeros are a
negligible perturbation of the companion matrix.
MAINT: Improve computation of gauss weights for hermite and hermite_e.

The new computations use normalized polynomials. Those polynomials are
less subject to overflow and allow the determination of the weights and
roots up to about degree 350, at which point the weights underflow.

Two private functions are added for computing the values of the
normalized polynomials:

1. _normed_hermite_n
2. _normed_hermite_e_n
BUG: remove static from function to avoid gcc-4.1 miscompile

gcc 4.1.2 (e.g. in red hat 5) will miscompile the function when
inlining. Without static it will not inline solving the issue.
Closes gh-5163
BUG: Make f2py work with intent(in out).

Note that Fortran ignores spaces in this case, so that 'in out' is
treated as 'inout'.

Closes #479.
TST: Add basic test for compiling with intent(in out).

This checks that the compilation works and that the expected error
is raised when non-contiguous arrays are passed as intent(in out).
Merge pull request #5167 from juliantaylor/rh5-miscompile

BUG: remove static from function
Merge pull request #5154 from charris/improve-gauss-hermite

Improve gauss hermite
Merge pull request #5168 from charris/f2py-space-fix

BUG: Make f2py work with intent(in out).
MAINT: replace bytewise copy with memcpy

memcpy takes care of unaligned memory and is inlined by the compiler,
there is no need for own code.
Merge pull request #5169 from juliantaylor/pyobjcopy-simplification

MAINT: replace bytewise copy with memcpy
ENH: allow auto vectorization of integer loops

Generalize the loop specializations with two new macros UNARY_LOOP_FAST
and BINARY_LOOP_FAST and apply it to more integer loops.
Same also gh-4561 which did this for integer boolean operations.
Merge pull request #5144 from juliantaylor/int-vectorize

ENH: allow auto vectorization of integer loops
MAINT: core: string constants in static buffers

Saves copying them into temporary buffers.
Merge pull request #5175 from larsmans/c-fixes

MAINT: core: string constants in static buffers