- correct an unquoted string (iosys) in PW/input.f90:483
(this was the cause of tonight compilation failere)
- correct a few incorrect format strings
- make more use of the constants module and thus
  provide more consistent units. NOTE, this has some
  numerical changes in the outputs, as in some places
  rather low precision and inconsistent numbers were
  used for unit conversion.
- convert all(?) single precision constants to double
  using the attached little perl program.
  exceptions: efermi.f90 (as it is supposed to be rewritten
  anyways), plotbands.f90 (it uses single precision everywhere,
  which may result in saving a significant amount of memory,
  so i converted the two double precision constants to single).
Unused routine 'set_fft_grid' removed


git-svn-id: http://qeforge.qe-forge.org/svn/q-e/trunk/espresso@3602 c92efa57-630b-4861-b058-cf58834340f0