* Moved several machine lifecycle callbacks to the notifier/subscriber
model. The old callback registration model is still available for
them for now, but prints a deprecation warning.
* Added pre-save/post-load notifications.
* Use a single allocated timer rather than one anonymous timer per
waiter. Waiters no longer prevent saved states from being loaded.
* Clean up outstanding waiters on stop or state load rather than just
leaking them.
* Started documenting parts of the emulator interface object that should
be relatively stable.
-imagedev/avivideo.cpp: Fixed an object leak on unload. Also changed
some other media image devices to use smart pointers.
Made autofire and inputmacro plugins capable of remembering settings if
the host input device for the binding is missing or if an input for a
slot device that isn't present is referenced.
* Moved common code for drawing about box, info viewer, and other text box menus to a base class; removed the last of the info viewer logic and the multi-line item hack from the base menu class.
* Added previous/next group navigation for general inputs and plugin input selection menus.
* Moved message catalog logic to lib/util, allowing osd and emu to use localised messages.
* Made the base menu class use the UI manager’s feature for holding session state rather than a static map and mutex.
* Improved menu event handling model, and fixed many issues, particularly with menus behaving badly when hidden/shown.
* Added better support for menus that don’t participate in the usual menu stack, like the menuless sliders and the save/load state menus.
* Made a number of menus refresh state when being shown after being hidden (fixes MT08121 among other issues).
* Fixed indication of mounted slot option in the slot option details menu.
* Improved appearance of background menus when emulation isn't running - draw all menus in the stack, and darken the background menus to make the edges of the active menu clearer.
* Fixed locale issues in -listxml.
-debugger: Made GUI debuggers more uniform.
* Added new memory view features to Win32 debugger.
* Fixed spelling of hexadecimal in Cocoa debugger and added decimal address option.
* Fixed duplicate keyboard shortcut in Cocoa debugger (Shift-Cmd-D was both new device window and 64-bit float format).
* Made keyboard shortcuts slightly more consistent across debuggers.
-plugins: Moved input selection menu and sequence polling code to a common library. Fixed the issue that prevented keyboard inputs being mapped with -steadykey on.
-docs: Started adding some documentation for MAME's internal UI, and updated the list of example front-ends.
-Regenerated message catalog sources. For translators, the new strings are mostly:
* The names of the inputs provided by the OS-dependent layer for things like fullscreen and video features. These show up in the user interface inputs menu.
* The names for automatically generated views. These show up in the video options menu - test with a system with a lot of screens to see more variants.
* The input macro plugin UI.
* A few format strings for analog input assignments.
* A few strings for the about box header.
-plugins: Sort input selection menus for autofire plugin.
-frontend: Fixed another case where the menus may not automatically
scroll the first item into view.
