Fixed a crash which occurred when overwriting a non-writable property.
Fixed an error in the RegExMatchObject creation code for callouts.
v1.1.16.04
Fixed x.y/[]/{} sometimes falsely being flagged as variadic.
Merge branch 'master' into alpha
Fixed returning ByRef vars.

StealMem from the right var.

`return var` is now always an expression, so aResultToken is set in all
cases by either ExpandExpression or ExpandArgs.  Static/global vars are
returned without copying (except by caller).  Local vars returned via
ByRef are left for ExpandExpression to copy into the deref buffer.
Fixed commands to treat objects as empty strings (not garbage).
Fixed a crash occurring when a for-loop expression causes thread-exit.
Begin converting Gui commands to object syntax, see details:

- GuiType now inherits from ObjectBase.
- Gui object lifetime is now managed like all other objects, i.e.
  script variables own it. The global Gui table is just a lookup table
  now. Destroying the object also destroys the Gui.
- Introduced GuiCreate([title, options, eventPrefix])
    (Event handling system not implemented yet)
- Introduced GuiFromHwnd(hwnd)
- Disabled Gui event label system in preparation for new event system
- Converted the following Gui commands to object syntax:
  - Gui Destroy -> gui.Destroy()
  - Gui Show -> gui.Show([options, title])
  - Gui Hide/Cancel -> gui.Hide()
  - Gui Minimize/Maximize/Restore -> gui.Minimize/Maximize/Restore()
  - Gui Font -> gui.SetFont([options, fontName])
  - Gui +/-Options... -> gui.Options("+/-Options...")
  - Gui Flash -> gui.Flash([enable])
  - Gui Margin -> gui.MarginX and gui.MarginY (properties)
  - Gui Color -> gui.BgColor and gui.CtrlColor (properties)
  - {retrieving HWND} -> gui.__Handle
  - {changing title} -> gui.Title
  The corresponding old Gui subcommands have been removed.
  Automatic Gui creation has also been disabled in the Gui command
  (in preparation for its complete removal, superseeded by GuiCreate).
- The following Gui options have been removed:
  - LastFound -> use WinWait or gui.__Handle instead
  - HwndOutputVar -> use gui.__Handle instead
  - Label -> superseeded by new event handling system
Gui: rename Text control to Label control
Remove GuiType::mName.
Store the GuiType object pointer inside HWNDs for faster retrieval.
Replace global Gui array with a linked list.
Remove Gui name system.
Begin replacing g-labels with new Gui event system
Convert most Gui events to use the new Gui event handling system
Refactor dialog owning to use a HWND instead of a Gui object
Convert GuiType::CustomCtrlWmNotify().
Gui: add OnClose() event return value: 0=close, non-0=don't close
Add parameter to GuiCreate() to control ownership of the event sink