It has never worked, I got confused here.

tests: fix volatile_state test

pmemobj_close is not thread safe and cannot be called concurrently with
pmemobj_direct.

disable drd test

disable concurrent_map_insert_reopen drd tests due to intermittent
failres (missing annotation, see issue https://github.com/pmem/libpmemobj-cpp/issues/770)

Fix sporadic DRD issue in concurrent skip list

concurrent_map: fix windows compilation

Fix Doxygen warnings in the concurrent_skip_list_impl.hpp

concurrent_map fixes

otherwise thread 11 and 12 might not start when we try to switch
to them in gdb script.

_size is a volatile variable and does not have to be flushed.
pmemcheck complained about missing flush in pmemkv tests.

Fix misleading warning message

add issue templates for GitHub interface

concurrent_map: fix windows compilation

On older MSVC versions sizeof(member) is not allowed in definition
of non-static members. Fix this by adding decltype().

Concurrent map data structure

Make pmem::allocator::allocate() throw exceptions in case of bad
allocation.
Make pmem::allocator::construct() throw exception if it is called
outside of transaction.

Implementation is based on concurrent skip list.
Ref:
https://www.cs.tau.ac.il/~shanir/nir-pubs-web/Papers/OPODIS2006-BA.pdf

tests: report error if binary is not built

Merge stable 1.9 into master

Cleanup CI files