Log Message:
Changes 3.1.1:
* Performance improvements for Intel EMT64.
* Performance improvements for large-size transforms with SIMD.
* Cycle counter support for Intel icc and Visual C++ on x86-64.
* In fftw-wisdom tool, replaced obsolete --impatient with --measure.
* Fixed compilation failure with AIX/xlc; thanks to Joseph Thomas.
* Windows DLL support for Fortran API (added missing __declspec(dllexport)).
* SSE/SSE2 code works properly (i.e. disables itself) on older 386 and 486
  CPUs lacking a CPUID instruction; thanks to Eric Korpela.