[lazarus] Updates

[Mattias Gaertner]

Hi all,

Updates:
- added mem manager for gtk-interface GDIObjects and DeviceContexts
- fixed heaptrc mem leaks of IDE/LCL
- fixed gdk_gc leaks
- accelerated synedit painting
- popupmenu items for bookmarks in source editor are now checked
- better theme support from Andrew: styles for LCL custom widgets can
  now be copied from any gtk widget type. For example the TSpeedButton
  now uses the style of gtkbutton. 
- form editing: renaming a form in the OI now renames the form and
  its class in the unit, changes the class name of the designed form
  and changes the CreateForm statement in the program source.
- minors: better bracket hilighting, fixed TMenuItem.AutoCheck,
  reduced freezing during compilation


Mattias