[Lazarus] Editor toolbar changes ?

[Juha Manninen]

Good news!
Trunk revision 49732 implements configurable ToolButtons with dropdown
lists. The design is from Ondrej Pokorny. It uses a new class
TIDEToolButton + polymorphism and integrates with TIDEMenuCommand.
The code that implements a specific button can be in a package. We
have a clean API now I dare to say.

Now it is used for 2 buttons, a Desktop selection and a JumpTo selection.
The JumpTo feature is interesting. It does not use the menu section as
I first envisioned, it adds the dropdown list to all JumpTo* commands.
It means you always get the dropdown list together with any of those
commands. It also means the used command works as a default action for
the button but the list is always the same.
I added JumpToImplementation button to the default configuration. It
is identical with the orignal Editor Toolbar now.

Graeme and Michael, please test.

Juha