Missing platform window features

[newk5]

These are not imgui specific. Some of these features would be very useful to have for the main window created by jimgui.

• [ ] Ability to disable/enable window maximize button
• [ ] Ability to disable/enable window minimize button
• [x] Ability to set the window title
• [ ] Ability to disable/enable window resizing

[ice1000]

Does https://github.com/ice1000/jimgui/blob/master/core/src/org/ice1000/jimgui/JImGui.java#L27 suffice?

[ice1000]

For the title stuff

[newk5]

Ah I didn't know about that. Thats helpful to set the title of the created window but would also be nice to be able to change it after it's created.

[ice1000]

Done set window title