Fix Freelook on Linux and add speed reset.

Should fix issue 7692.
Also fixes issue 7147.

I have no idea if these changes will affect Mac or Windows users, so please test.
Update freelook description.
Reorganize faulting stuff.  Differentiate between arch- and OS-specific defines.

- Get rid of ArmMemTools.cpp and rename x64MemTools.cpp to MemTools.cpp.
  ArmMemTools was almost identical to the POSIX part of x64MemTools, and
  the two differences, (a) lack of sigaltstack, which I added to the
  latter recently, and (b) use of r10 to determine the fault address
  instead of info->si_addr (meaning it only works for specifically
  formatted JIT code), I don't think are necessary.  (Plus Android, see
  below.)

- Rename Core/PowerPC/JitCommon/JitBackpatch.h to Core/MachineContext.h.
  It doesn't contain anything JIT-specific anymore, and e.g. locking
  will want to use faulting support regardless of whether any JIT is in
  use.

- Get rid of different definitions of SContext for different
  architectures under __linux__, since this is POSIX.  The exception is
  of course Android being shitty; I moved the workaround definition from
  ArmMemTools.cpp to here.

- Get rid of #ifdefs around EMM::InstallExceptionHandler and just
  provide an empty implementation for unsupported systems (i.e.
  _M_GENERIC really).  Added const bool g_exception_handlers_supported
  for future use; currently exception handlers are only used by the JIT,
  whose use implies non-M_GENERIC, but locking will change that.

- Remove an unnecessary typedef.
DolphinWX: Kill off trivial event tables

Also fixes some of the wonky stuff in Main where we would fire an event to do post-init stuff which isn't necessary anymore.
DVDInterface: Initialize variables
Explicitly turn off Rift when shutting down direct mode.
On my computer none of the direct to rift applications switch off the Rift when you exit, except Dolphin now.
Merge branch 'VR-Hydra' of https://github.com/cegli/dolphin into VR-Hydra
Automatic translation template update
Automatic translation resources update from Transifex
Revert "Automatic translation resources update from Transifex"

This reverts commit 3270f497894cfbec91051ed1ccea3994acb880a4.
JIT: add 64-bit write support to FIFO functions

Also fix 64-bit values passed to CallAC and otherwise correct immediate
handling in FIFO writes.
Fixes 007 Nightfire.
Merge branch 'master' of https://github.com/dolphin-emu/dolphin into VR-Hydra
Install nogui executable to bindir
Merge pull request #1524 from Parlane/fix_nogui_install

Install nogui executable to bindir
Merge branch 'master' of https://github.com/dolphin-emu/dolphin into VR-Hydra
Fix specfile for nogui executable

Support new nogui executable in specfile as dedicated sub-package.
Merge pull request #1518 from lioncash/evt

DolphinWX: Kill off trivial event tables
Fail CMake if building WX without GTK libraries.
NetPlayDiag: Make the window title translateable
JIT: revert accuracy improvement to mftb

Fixes a few games (e.g. Karaoke Revolution Party) for reasons explained in the
comments.