Merge pull request #1 from MatterHackers/master

Updated code from Master
Fixed export windows in Print Queue Item and Library Item from opening multiple times. I also added a test for adding ".stl" and ".gcode" file extensions and did more localization.
Merge remote-tracking branch 'upstream/pr/5'
Localization, Export Windows, Extension Test
Corrected problems with the view window Print Item

Every time the "view" link on a "print queue item" is clicked a new
window would open. I made changes so that it only opens once regardless
of how many times it is clicked on.
Made Adjustments to view window in Print Library

Adjusted code in Print Library for the view window so that any given
window can only be opened once regardless of how many times the user
selects the view link.
More Localization

Fixed the translation for the queue widget on main slide panel and also
added translation for printer connection status on Action Bar.  Made
corrections to previously modified strings.
Merge remote-tracking branch 'Greg's_Fork/master' into development
Turned off localization debug.
Localized two strings.