Rollback the bootstrap.inc changes in last commit. They were ill advised. Drupal needs to delay its redirect to install.php (as it was in D7) we Drush stops working well on not-yet-installed sites.
Use full command name instead of alias.
Delete the cached file as well when a download is MD5 corrupt
Use drush_get_user_id() in Drush Batch API. Clean up batchTest.php.
Fix warnings introduced in cbfc412ddac8832d2aac87b64ec333cf7d93bc50.
#194: runserver / quick-drupal fails in drupal 8.
#194: runserver / quick-drupal fails in drupal 8. Fix runserver-prepend.php.
Use \Drupal::currentUser() instead of global $user.
Also avoid caching updatexml when a download fails MD5 verification.
#231: Update watchdog commands for D8
#232: Update queue commands for D8
Docstring fix.
Remove a couple of unneeded return statements.
Updating contrib destination test to include a theme.
User engine is not loaded at drush updb.

This makes the command to crash on Drupal 7 with the following error:

Error: Call to undefined function drush_get_user_id() in /usr/share/drush/includes/batch.inc, line 72
Fix #250. drush help --format=json now prints output only once. Also fixed help to note that var_export is a supported output format as well. This bug was a byproduct of f4b68b66d7fd16e3f0ad2c2c640889f330f19141. The help command's usage of the outputformat system is unusual.
Merge pull request #251 from juampy72/missing-user-engine-at-drush-updb

User engine is not loaded at batch.inc (error in updb).
Fix #249. Update pm-download and friends with the new XML update format. Please test this so I can backport to 6.x
Re-add the config-export command. For now it is a wrapper around core-rsync.
Updating file-extract test to use more stable library source.