Changed location of vendor specific thumbnail images of printers:

These images are newly stored inside the resources/profiles/VENDOR_NAME/,
they should be named by the printer_model identifier suffixed with
"_thumbnail.png"

All the existing printer thumbnails were moved and renamed,
thumbnails for the 3rd party printers were added, marked as Beta.

resources/profiles/LulzBot.idx

@@ -0,0 +1,2 @@
+min_slic3r_version = 2.2.0-alpha3
+0.0.1 Initial version

resources/profiles/LulzBot.ini

@@ -2,9 +2,9 @@
 
 [vendor]
 # Vendor name will be shown by the Config Wizard.
-name = Lulzbot
+name = LulzBot
 config_version = 0.0.1
-config_update_url = http://files.prusa3d.com/wp-content/uploads/repository/PrusaSlicer-settings-master/live/Lulzbot/
+config_update_url = http://files.prusa3d.com/wp-content/uploads/repository/PrusaSlicer-settings-master/live/LulzBot/
 
 [printer_model:MINI_AERO]
 name = Mini Aero

src/slic3r/GUI/ConfigWizard.cpp

@@ -188,7 +188,7 @@ PrinterPicker::PrinterPicker(wxWindow *parent, const VendorProfile &vendor, wxSt
 
         wxBitmap bitmap;
         int bitmap_width = 0;
-        const wxString bitmap_file = GUI::from_u8(Slic3r::var((boost::format("printers/%1%_%2%.png") % vendor.id % model.id).str()));
+        const wxString bitmap_file = GUI::from_u8(Slic3r::resources_dir() + "/profiles/" + vendor.id + "/" + model.id + "_thumbnail.png");
         if (wxFileExists(bitmap_file)) {
             bitmap.LoadFile(bitmap_file, wxBITMAP_TYPE_PNG);
             bitmap_width = bitmap.GetWidth();