Merge pull request matplotlib#2743 from cimarronm/macosx_show_orderfront

Updated the macosx backed figure manager show function to bring the window to the front.

Author: pelson

src/_macosx.m

@@ -3993,6 +3993,7 @@ static void _data_provider_release(void* info, const void* data, size_t size)
     {
         NSAutoreleasePool* pool = [[NSAutoreleasePool alloc] init];
         [window makeKeyAndOrderFront: nil];
+        [window orderFrontRegardless];
         [pool release];
     }
     Py_INCREF(Py_None);