[USETUP] Some fixes/improvements suggested by Thomas (1/2).

[USETUP] Some fixes/improvements suggested by Thomas (1/2).

- isspace('\0') returns FALSE anyways so no need to separately test for a NULL character;
- The (str/wcs)toul function cannot return a NULL pointer from its second paramter;
- VersionInfo32_FindChild(): the third argument is indeed a number of characters (not bytes),
  so rename the parameter to make this fact clear. The function is however correctly used within this module.

svn path=/branches/setup_improvements/; revision=74629