Apply cpplint to src and add lint to test.sh

LICENSE

include/agent/windows/get_time.h

src/linux/get_date.cpp

src/linux/get_distro.cpp

src/linux/get_macaddr.cpp

src/linux/get_machine_type.cpp

src/linux/get_time.cpp

src/linux/get_user_count.cpp

src/linux/inventory.cpp

src/main.cpp

src/network_bandwidth.cpp

src/post.cpp

src/user_history.cpp

src/windows/get_date.cpp

src/windows/get_macaddr.cpp

src/windows/get_machine_type.cpp

src/windows/get_time.cpp

src/windows/inventory.cpp

test/test.sh