New threadpool

- removed some whitespace noise.
 - cleaned up CMakeLists.txt
 - reintegrated task_manager.c into thread-pool.c
 - cleaned up some unnecessary code

Co-authored-by: Cedric Roux <cedric.roux@eurecom.fr>
Co-authored-by: Mikel Irazabal <mikel.irazabal@openairinterface.com>

common/utils/telnetsrv/telnetsrv.c

@@ -53,7 +53,6 @@
 #include <sys/resource.h>
 #include "common/utils/load_module_shlib.h"
 #include "common/config/config_userapi.h"
-#include "common/utils/threadPool/thread-pool.h"
 #include "executables/softmodem-common.h"
 #include <readline/history.h>
 #include "common/oai_version.h"