update gantry to v4.1.19

Release Notes - Gantry Joomla Framework - Version 4.1.19

Bug
• registration form layout issue
• Preview module positions causes broken Gantry template edit link
• ACL Bug when editing article on frontend
• language strings issue for fixed layout types
• Removed RocketTheme references in Copyright Feature
• Advanced search instructions not showing in J3.X
• Fixed js errors in template manager with IE11 that were preventing the normal use of admin
• Incorrect leading articles count in Joomla Category Blog view for Joomla 3.2
• Missing 2-Factor Authentication field in mod_login Joomla 3.2 override
• 960 Fixed option overflow issues
• font style issues caused by fontawesome icons
• IE11 is not being detected correctly
• Minor typo in gantryjson.class.php (Lahmizzar Muinela)

Improvement
• 3.1 support for custom overrides
• SUGGESTION: add meta tag to header to force IE to use highest version of browser
• Front end Gantry cache not being cleared on Gantry Template Cache clear or save

New Feature
• No special characters with google fonts - solution
• Template error.php file needs to be translatable.