[LYN-2522] Filtering for gem catalog (#867)

* Added sort filter proxy model for gem model that can filter based on name, gem origin, supported platform, features and/or types.
* Added new filter pane on the left with several filter categories for gem origin, type, platform and feature.
* Added filter category widget which is a collapsable generalized checkbox group that can interact with the proxy model and thus control filtering.
* Removed fixed size of the project manager. The application should always be resizable.

Code/Tools/ProjectManager/Source/GemCatalog/GemInfo.cpp

@@ -62,6 +62,19 @@ namespace O3DE::ProjectManager
         }
     }
 
+    QString GemInfo::GetGemOriginString(GemOrigin origin)
+    {
+        switch (origin)
+        {
+        case O3DEFoundation:
+            return "Open 3D Foundation";
+        case Local:
+            return "Local";
+        default:
+            return "<Unknown Gem Origin>";
+        }
+    }
+
     bool GemInfo::IsPlatformSupported(Platform platform) const
     {
         return (m_platforms & platform);