Correct name of Archive::Tar::Constant module, and note "type" is available in list_archive

Chris,

Please find inline a patch for a couple of small documentation fixes
for Archive::Tar.  Let me know if you'd like the suggested change to
be submitted in a different way.

  cheers, Tom Jones.

Signed-off-by: Chris 'BinGOs' Williams <chris@bingosnet.co.uk>
Update CHANGES and bump to version 1.90