Add pthread support to threading abstraction.
Sanitizer
run_thread_sanitizer
[ 66%] Building CXX object test/CMakeFiles/tests.dir/main.cpp.o
[ 77%] Building CXX object test/CMakeFiles/tests.dir/example_tests.cpp.o
[ 88%] Building CXX object test/CMakeFiles/tests.dir/thread_tests.cpp.o
[100%] Linking CXX executable ../bin/tests
[100%] Built target tests
===============================================================================
All tests passed (5 assertions in 4 test cases)
ERROR: Job failed: exit code 1