[Lazarus] Change default component name

[Michalis Kamburelis]

Mattias Gaertner wrote:
>> To answer my own question, the logic is inside
>> TCustomFormEditor.CreateUniqueComponentName,
> 
> I added a check. Please test.

New ClassNameToComponentName works fine :), tested with Lazarus trunk
compiled by FPC 2.4.4. The default component name is now "T3DScene1",
which makes it a valid identifier.

>>
>> I guess the class should just be renamed.
> 
> Yes, that would be nicer for many users.
> 

Will do. (I want to support at least Lazarus 0.9.30 anyway, so even if
Lazarus trunk will get nicer solution, I still have to workaround it for
existing stable Lazarus version.)

Thanks,
Michalis