runs on platforms with GNU tar installed
* the "pear" script now requires a command parameter (similar to cvs),
for example "pear package Cache.xml"
* broke PEAR_Installer :-)
* PEAR_Error moved into PEAR.php to reduce the number of files that are
always included
* cleaned up the PEAR_Error API a bit and changed the two classes using it
* added PEAR_Installer - an administration class for installing packages
and maintaining a "class/file cache"