catch exceptions in savestate load

see also #2090. This can reasonably catch and handle simple load failures like all waterbox loads and some others.

Not calling the issue fixed because there is more that can be done to prevent cores from trying to load invalid savestates.

src/BizHawk.Client.Common/savestates/SavestateFile.cs

@@ -147,7 +147,14 @@ namespace BizHawk.Client.Common
 
 			using (new SimpleTime("Load Core"))
 			{
-				bl.GetCoreState(br => _statable.LoadStateBinary(br), tr => _statable.LoadStateText(tr));
+				try
+				{
+					bl.GetCoreState(br => _statable.LoadStateBinary(br), tr => _statable.LoadStateText(tr));
+				}
+				catch (Exception)
+				{
+					return false;
+				}
 			}
 
 			// We must handle movie input AFTER the core is loaded to properly handle mode changes, and input latching