Makes the information panel self-contained.

This was done first, as opposed to isolating the GameConfig panel--the
first panel in the group--as this panel had code all over the place in
ISOProperties, so I figured it'd be best to fix this one up first.

And related ARCodeAddEdit/PatchAddEdit.

Change ISOFile to use wxImage instead of wxBitmap since bitmaps require
a screen context and banner images have a fixed resolution.

If the user enables a cheat while cheats are globally disabled then
display a notice about it. Issue 9690.

Refactor Action Replay code into its own class like Gecko Codes.

At first there weren't many enums in Volume.h, but the number has been
growing, and I'm planning to add one more for regions. To not make
Volume.h too large, and to avoid needing to include Volume.h in code
that doesn't use volume objects, I'm moving the enums to a new file.
I'm also turning them into enum classes while I'm at it.

ISOProperties no longer needs its hack to refresh the game list, the
new INI Modified event can be used instead.

Cleanup code style.

Move ActionReplay code->INI saving into ActionReplay namespace.

Threadsafety Cleanup: ActionReplay is accessed from the Host, Emu
and CPU Threads so the internal storage needs to be protected by a
lock to prevent vectors/strings being deleted/moved while in use by
the CPU Thread.

UI Consistency: Make ARCodes behave like Gecko Codes - only apply
changes when Apply is pressed. Save changes to INI from CheatsWindow.

ISOProperties/CheatsWindow now synchronize with each other.

ISOProperties loads codes using ActionReplay::LoadCodes which actually applies
the codes to the global state. If a game is running then that games receives
all the codes (and ACTIVE status) from the second game being shown in
ISOProperties which is not desirable.