use short-form when loading small integers

.hgignore

@@ -3,3 +3,5 @@ bin/*
 obj/*
 /*.user
 glob:Dapper/NuGet.exe
+syntax: glob
+*.docstates

Dapper/SqlMapper.cs

@@ -816,7 +816,7 @@ private static void EmitInt32(ILGenerator il, int value)
                 case 6: il.Emit(OpCodes.Ldc_I4_6); break;
                 case 7: il.Emit(OpCodes.Ldc_I4_7); break;
                 case 8: il.Emit(OpCodes.Ldc_I4_8); break;
-                default: il.Emit(OpCodes.Ldc_I4, value); break;
+                default: il.Emit(value >= -128 && value <= 127 ? OpCodes.Ldc_I4_S: OpCodes.Ldc_I4, value); break;
             }
         }