- Fix a nasty bug where pkg_create doesn't gzip package if lengh of package

- Fix a nasty bug where pkg_create doesn't gzip package if lengh of package
  name is less than 5 and doesn't contain recognizeable suffix (one of .tar or
  .tgz), while gzip's it if lengh of the name greater than 4. For example
  `pkg_create [options] pkg1' will create pkg1.tar, while
  `pkg_create [options] pkg11' will create pkg11.tgz;
- use TRUE/FALSE as a values for boolean variables instead of explicit 1/0 and
  erroneous YES in one case.

MFC candidate.