drush 8.x-6.0-rc2

Changes since 8.x-6.0-rc1:

• #2041109 by greg.1.anderson: Make Drush call command hooks more consistently.
• #1957934 by helmo | moshe weitzman: Added Updatedb should support output format.
• #2034731 by helmo: Fixed Collected code style fixes.
• #2031383 by ergonlogic: Added Provide weight-like mechanism to ensure order of hook calls.
• #2021607 by greg.1.anderson, rballou: Drush sql-cli database flag.
• #2027165 by dawehner: Added the --druplicon global option. Try it!.
• #2041875 by greg.1.anderson: "Invalid argument supplied for foreach() pm.drush.inc:593" warnings with 'drush ups'
• #2042719 by kostajh: db-url should be a global option.
• #2041109 by greg.1.anderson: Added Make Drush call command hooks more consistently.
• Use getOutputFromJSON() in cache tests
• #2043057 by dmitry_bezer: Fixed archiveDumpCase test fails on windows.
• #1748228 by greg.1.anderson, Shaun Dychko | rob.black: Added Error in the PHP config setting of magic_quotes_gpc() prevents diagnosis of the problem through drush core-status.
• Remove some errors when using --simulate with site-install
• #2043661 by kostajh: Fixed _drush_sql_get_db_table_list() should not print out table list.
• Use 'integrate' => FALSE when pm-updatecode calls into pm-updatestatus.
• #2030311 by helmo: Fixed testUnknownOptions fails on PHP 5.4.
• #2041165 by greg.1.anderson, greggles: Overlapping jobs - files getting clobbered in sql-sync?
• #2042565 by greg.1.anderson | moshe weitzman: Fixed @self alias is missing its path-aliases definitions.
• 2042575 by greg.1.anderson: Fix site database credential caching, so that Drush sql-sync will not call sql-conf more times than necessary.
• Remove a few lingering references to #id
• #2043891 by greg.1.anderson | Jim Bacon: Fixed Use command-specific alias options when using a group alias.