Patch ARPACK for fortran calling convention to be consistent with MKL.

[ViralBShah]

This patch was obtained from macports: http://trac.macports.org/ticket/35508

This also sets the environment variable for the ILP64 MKL upon startup, if USE_BLAS64=1

See #3928 JuliaLang/LinearAlgebra.jl#53

[StefanKarpinski]

the indentation here is a bit weird

[ViralBShah]

It was some emacs mode weirdness, but I already fixed it.

[ViralBShah]

Cc: @vtjnash

[ViralBShah]

@vtjnash Would we be better off just compiling all our fortran code with -ff2c instead of applying this patch to ARPACK?

[vtjnash]

@ViralBShah yes, it's better to compile with -ff2c.

it seems that this patch only patches half of the issue -- it neglects to correct the calling convention return types for sasum, scasum, scnrm2, sdot, sdsdot, and snrm2 for which there is no way to specify the f2c calling convention using gfortran. plus, it neglects to patch any calls into lapack (although since we have our own lapack, that's less of a problem)

I would suggest making separate binaries libarpack_f2c liblapack_f2c libsuitesparse_f2c etc. instead

[ViralBShah]

How about just always compiling everything fortran with -ff2c by default?

[vtjnash]

Yes. Although (a) we need Julia to support the intel calling convention #2167 (b) we need to check that the other libraries (arpack, fftw, suitesparse) are aware of the f2c calling convention and ILP64 interface.

[ViralBShah]

The ARPACK patch from macports does not crash our ARPACK tests. Using -ff2c everywhere instead of using the macports patch does not help, and continues to crash, or make the tests fail.

Does Intel have a different fortran calling convention and not use f2c?

[ViralBShah]

Would this work with Accelerate if we disable gfortblas?

[andreasnoack]

If we manage to use libmkl_gf_(i)lp64 then we could use the gfortran convention everywhere, right?

[ViralBShah]

Agree.

[ViralBShah]

I have pared down this PR to include some small fixes. Will try linking to the gfortran version of libmkl in a separate PR.