Core: Use a std::string in EXI_DeviceIPL instead of a char buffer

Allows getting rid of extra code.
Fix D3D Real XFB texture sampling.
Common: State OS instead of 32/64 bit in the netplay lobby
CFrame: Check borderless fullscreen setting before enabling exclusive fullscreen in the video config.

Fixes a bug where "Use Fullscreen" would initialize into exclusive fullscreen regardless of the borderless fullscreen setting.

Also relieves the need for the video renderer to check the borderless fullscreen setting each time.
CFrame: Don't check the video config fullscreen setting.

Checking this flag could sometimes incorrectly have the UI assume fullscreen is already off when we're still exiting.
VideoConfig: Ignore Borderless Fullscreen setting when the backend does not support exclusive fullscreen.

This was expected to be handled by VerifyValidity(), but that only verifies the validity of the INI files.
x64Emitter: Fix REX encoding for SETcc

Previously using the new "lower 8 bits" registers (SIL, SPL, ...) caused SETcc
to write to other registers (for example, SETcc SIL would generate SETcc DH).
Disable Holodeck Safety Protocols!
Use a dialog box instead of the Health and Safety screen.
(You need to disable HWS in LibOVR yourself, it's not part of this project.)
Merge pull request #690 from Armada651/d3dfullscreen_fixes

Exclusive fullscreen fixes
DolphinWX: Remove the Projection Hack UI
Fix PPC_FP on non-sse4.1 code paths.

The Invalid bit on the x87 fpu is sticky, so once a single NaN goes
through the old code on CPUs without sse4.1 all future floats are
mutilated.

Patch to emulate PTEST by Fiora.

Fixes issue 7237 and issue 7510.
Merge pull request #681 from phire/non-sse4_1

Fix PPC_FP on non-sse4.1 code paths.
Optimize PPC CR emulation by using magic 64 bit values

PowerPC has a 32 bit CR register, which is used to store flags for results of
computations. Most instructions have an optional bit that tells the CPU whether
the flags should be updated. This 32 bit register actually contains 8 sets of 4
flags: Summary Overflow (SO), Equals (EQ), Greater Than (GT), Less Than (LT).
These 8 sets are usually called CR0-CR7 and accessed independently. In the most
common operations, the flags are computed from the result of the operation in
the following fashion:
  * EQ is set iff result == 0
  * LT is set iff result < 0
  * GT is set iff result > 0
  * (Dolphin does not emulate SO)

While X86 architectures have a similar concept of flags, it is very difficult
to access the FLAGS register directly to translate its value to an equivalent
PowerPC value. With the current Dolphin implementation, updating a PPC CR
register requires CPU branching, which has a few performance issues: it uses
space in the BTB, and in the worst case (!GT, !LT, EQ) requires 2 branches not
taken.

After some brainstorming on IRC about how this could be improved, calc84maniac
figured out a neat trick that makes common CR operations way more efficient to
JIT on 64 bit X86 architectures. It relies on emulating each CRn bitfield with
a 64 bit register internally, whose value is the result of the operation from
which flags are updated, sign extended to 64 bits. Then, checking if a CR bit
is set can be done in the following way:
  * EQ is set iff LOWER_32_BITS(cr_64b_val) == 0
  * GT is set iff (s64)cr_64b_val > 0
  * LT is set iff bit 62 of cr_64b_val is set

To take a few examples, if the result of an operation is:
  * -1 (0xFFFFFFFFFFFFFFFF) -> lower 32 bits not 0       => !EQ
                            -> (s64)val (-1) is not > 0  => !GT
                            -> bit 62 is set             =>  LT
            !EQ, !GT, LT

  *  0 (0x0000000000000000) -> lower 32 bits are 0       =>  EQ
                            -> (s64)val (0) is not > 0   => !GT
                            -> bit 62 is not set         => !LT
            EQ, !GT, !LT

  *  1 (0x0000000000000001) -> lower 32 bits not 0       => !EQ
                            -> (s64)val (1) is > 0       =>  GT
                            -> bit 62 is not set         => !LT
            !EQ, GT, !LT

Sometimes we need to convert PPC CR values to these 64 bit values. The
following convention is used in this case:
  * Bit 0 (LSB) is set iff !EQ
  * Bit 62 is set iff LT
  * Bit 63 is set iff !GT
  * Bit 32 always set to disambiguize between EQ and GT

Some more examples:
  * !EQ, GT, LT -> 0x4000000100000001 (!B63, B62, B32, B0)
                -> lower 32 bits not 0          => !EQ
                -> (s64)val is > 0              =>  GT
                -> bit 62 is set                =>  LT
  * EQ, GT, !LT -> 0x0000000100000000
                -> lower 32 bits are 0          =>  EQ
                -> (s64)val is > 0 (note: B32)  =>  GT
                -> bit 62 is not set            => !LT
CR: Replace some magic values with constants.
Initial unoptimized JITIL flag optimization.
JITIL: Optimize compare instruction.
JITIL: optimize branches.
JITIL: compare instruction folding.
JitIL: Misc small optimizations.
JitIL: Attempt to constant-fold more aggressively.