Fix bug that causes endless loop in queue (next not set to NULL in case we insert a reply state into the queue for the second time).

Giving device_mgr a fish name :-).

--HG--
branch : octopus.add-device-mngr
rename : usr/device_mgr/Hakefile => usr/kaluga/Hakefile
rename : usr/device_mgr/main.c => usr/kaluga/main.c
rename : usr/device_mgr/queue.c => usr/kaluga/queue.c
rename : usr/device_mgr/queue.h => usr/kaluga/queue.h

Renaming device manager

--HG--
branch : octopus.add-device-mngr