Don't write to EXRAM if it doesn't exist.

Previously, if a gamecube game wrote to an EXRAM address, dolphin would
segfault.
Panic on invalid reads/writes for non-mmu games.

Previously it would fall through to the mmu code path, and raise a dsi
exception, which it would never check for, so it would continue
executing code silently.
DolphinWX: Split cheat window components into their own source files
CheatsWindow: Remove unnecessary wxPanel in the wxDialog

We can simply size the controls within the dialog directly.
DolphinWX: Reimplement cheat listbox updating, but without a global

Just use event handling.
CheatsWindow: unfriend CreateCodeDialog.

This is no longer needed.
Clamp the AX Volume to prevent clipping.  Patch by hk.konpie.  Fixes issue 7519.
Disable skip bios option if no bios files exists.
Merge pull request #1318 from RachelBryk/disable-bios

Disable skip bios option if no bios files exists.
Merge pull request #1334 from lioncash/cheats

Break Cheat Manager components out into their own source files.
Merge pull request #1337 from skidau/AX-volume-clamp

Clamp the AX Volume to prevent clipping.  Patch by hk.konpie.  Fixes issue 7519.
D3D: Enabled depth clipping
Merge pull request #991 from phire/dsi_should_crash

Panic if game does an invalid memory access.
Merge pull request #1346 from kayru/d3d_clip_enable

D3D: Enabled depth clipping
Add BitSet and, as a test, convert some JitRegCache stuff to it.

This is a higher level, more concise wrapper for bitsets which supports
efficiently counting and iterating over set bits.  It's similar to
std::bitset, but the latter does not support efficient iteration (and at
least in libc++, the count algorithm is subpar, not that it really
matters).  The converted uses include both bitsets and, notably,
considerably less efficient regular arrays (for in/out registers in
PPCAnalyst).

Unfortunately, this may slightly pessimize unoptimized builds.
Convert registersInUse to BitSet.
Add workaround for OS X symbol clash and AllOnes helper method.
Convert some VideoCommon stuff to BitSet.

Now with a minor performance improvement removed for no reason.
Add unit test.