Fix the date time set in file by removing the ':'.

This is the same code than the one under SendCore. The date time should
not have the : (time zone offset) to be able to use the file.
[Mono.Parallel] Removed broken Mono.Threading.Tasks code

The code in MonoTaskExtensions.cs relied on the internal method Execute(Action<Task>) in System.Threading.Tasks.Task which was removed in 0a66e60.
Added stress test to ConcurrentQueue.TryPeek.
The test checks that in some race condition the queue does not return null.
Changed TryPeek to handle race condition with Dequeue.
Dequeue sets the head.Value to its default. When TryPeek is interrupted in the process of retrieving the value some times Dequeue sets the value to its default. TryPeek now checks the head has not been changed before returning the value.
Remove a #warning in security.c which gets triggered on OS X.
Fix a warning in atomic.c.
Disable `perf` support in the profiler when running on Android (for now).

We need to assess the situation before we enable this everywhere. Apparently
some older devices have trouble with `perf`.
[x86] Arguments to calls are passed via moves, instead of pushes.

I release these changes under the MIT license.
[arm] Fix OP_ATOMIC_CAS_I4.
Revert "Fix a warning in atomic.c."

This reverts commit 1fdc8789a7f4bfc6fa7f67c126569765194a3b6c.

This breaks the ios build:

../../../../../mono/mono/utils/atomic.c: In function ‘InterlockedCompareExchange64’:
../../../../../mono/mono/utils/atomic.c:572: error: ‘spin’ undeclared (first use in this function)
../../../../../mono/mono/utils/atomic.c:572: error: (Each undeclared identifier is reported only once
../../../../../mono/mono/utils/atomic.c:572: error: for each function it appears in.)
Merge branch 'master' of github.com:mono/mono
Mark the `spin` variable in atomic.c as G_GNUC_UNUSED.

It would require an `#ifdef` forest to get the conditions
under which it is used right.
Bring the implementation of the 64-bit CAS fallback in line with the 32-bit one.
Fix the build. We've been missing this include for ages...
Revert unintentional change.
Compile libgc with -Wno-deprecated-declarations as it uses some obsolete POSIX APIs.
Disable -Wreturn-local-addr in libgc/mark_rts.c!GC_approx_sp with GCC 4.8.0+.
Disable -Warray-bounds in eglib/src/sort.frag.h!insert_list in GCC 4.6.0+.
Mark an unused variable as such in eglib/test/file.c.
Add missing prototypes in ikvm-native.