Log Message:
Update to psftools-1.0.7.

* Codepages: The PPCGREEK codepage had the two lower-case sigmas the
  wrong way round. Various other corrections made to the PPCGREEK and
  PPC860 codepages.

* psf2bbc: Converts a PSF font to a BBC Micro soft font.
* bbc2psf: Reverses psf2bbc; converts a BBC Micro soft font to PSF.
* The BBCMICRO codepage now covers characters 32-255.