Kill support for the ancient FPA format on ARM.
Remove an unused variable in verify.c.
Add a missing IS_VFP check for OP_FCLT in the ARM back end.
Enable hw division/remainder on mt in non-thumb mode as well.
Improve the size of the arm SEQ_POINT implementation a bit.
Use the native unwinder when Exception::ToString throws.

	* exception.c: Add mono_exception_get_managed_backtrace so the code that
	deals with unhandled exceptions can produce some stacktrace in case
	Exception::ToString itself produces another exception.

	This can happen under multiple situations, be it OOM, heap corruption or
	bugs in ToString ().
Space/tabs unification
Simply logic a bit when SslClientStream is only used from inside System.dll
[xbuild]: Fix 4.0/4.5 repo layout.

4.0/Microsoft.Common.* was not installed anywhere, so it could safely
be deleted, and 4.5/M.C.* was previously being installed into
$(prefix)/lib/mono/4.0.  It's now in 4.0/M.C.* to match xbuild's
tool version.

This patch does not affect how things are installed, it simply cleans
up the source layout.
[xbuild]: Define TargetingClr2Framework.
Clean up the partial generic sharing code a bit.
Disable a corlib test which can fail on some systems.