Added handle argument to drush_print_table so it won't interfere with test output, removed file argument since we're not using it anywhere.

#992554 by greg.1.anderson: Improve drush function names for functions where drush calls back in to drush

#861822 by greg.1.anderson: Add an option to sanitize email addresses and passwords from user table post sql-sync.

#694036 by mikeryan. print a timers table at end of debug log. i'm open to alternate ways of triggerring the printing of this table.

#687724 - multithreaded updatedb command, by forking and simplifying the batch api from drupal core. this is implemented for d6 and d7. also implement a hidden flag on commands so they do not appear on help. this drastically reduces memory requirements

#460924 by greg.1.anderson. remove prepare-script and slave database features from new sql sync command.

#460924 by greg.1.anderson. Site aliases may be defined in drushrc.php or on command line. These are used to run any drush command on a remote server via ssh. The improved rsync and new sql sync commands are fine examples. sql sync dumps a local or remote db, gzips, rsyncs, and then imports. We now have fast, database migration from prod => dev or vice versa.

#586466. Remove shebang from drush.php. You should use the drush scell script, or call 'php drush.php' instead.

#581870 by moshe weitzman. 'Your command line PHP installation is too old. Drush requires at least PHP ' . DRUSH_MINIMUM_PHP

Automatically log values for all timers at end of command. Requires --debug to see them. useful for commands like migrate that use drupal's timer API.

#503328 - fix drush cron due to drush shutdown exiting. register exit helper in drush_shutdown. Thanks david goode

#453948 - Moved PHP version check to drush.php, since environment.inc try/catch doesn't parse in php4. At some point we could move this to an engine, if we find enough cases to make it worthwhile.

#434772 - drush return codes are the opposite of expected unix command return codes. drush now returns 0 on success. If the shutdown handler is triggered before drush has completed, it now triggers an error.

Add new global option, --pipe, which send back output intended to be used in a script. Implemented by statusmodules command in order to send back a space delimited list of enabled modules.

#449090 by Grugnog2. Major improvements in error messaging around: The command 'drush.php ... could not be executed.

#413502 by aexl_konzepto.net and fgm. cli test fails: drush.php is designed to run via the command line