Remove unused scoped_unlock, unlock_guard_try

[K-ballo]

No description provided.

[hkaiser]

Should we add a

#if defined(HPX_HAVE_SCOPED_LOCK_COMPATIBILITY)
template <typename Lock>
using scoped_unlock<Lock> = unlock_guard<Lock>;
#endif

and follow the usual deprecation steps instead of just dropping scoped_unlock without proper phasing-out?

[K-ballo]

Should we add a

#if defined(HPX_HAVE_SCOPED_LOCK_COMPATIBILITY)
template <typename Lock>
using scoped_unlock<Lock> = unlock_guard<Lock>;
#endif

and follow the usual deprecation steps instead of just dropping scoped_unlock without proper phasing-out?

Sounds good, specially if compatibility defaults to OFF.

[K-ballo]

Added deprecation compatibility flag.

[hkaiser]

Perfect, thanks!