[travis] travis tests failing randomly about care-o-bot HOT 2 CLOSED

run-parts: executing /etc/kernel/header_postinst.d/dkms 3.13.0-105-generic /boot/vmlinuz-3.13.0-105-generic
Creating symlink /var/lib/dkms/uvcvideo/1.1.1-3-realsense/source ->
                 /usr/src/uvcvideo-1.1.1-3-realsense
DKMS: add completed.
Error! Your kernel headers for kernel 4.4.0-51-generic cannot be found.
Please install the linux-headers-4.4.0-51-generic package,
or use the --kernelsourcedir option to tell DKMS where it's located
WARNING: DKMS module failed to installed; removing...
------------------------------
Deleting module version: 1.1.1-3-realsense
completely from the DKMS tree.

catkin_make -DCMAKE_BUILD_TYPE=Release install > /dev/null #2>&1
make[3]: warning: jobserver unavailable: using -j1.  Add `+' to parent make rule.
make[3]: warning: jobserver unavailable: using -j1.  Add `+' to parent make rule.
make[3]: warning: jobserver unavailable: using -j1.  Add `+' to parent make rule.
Makefile:102: *** "Can't find /usr/src/linux-headers-4.4.0-51-generic/include/linux/version.h".  Stop.
Makefile:102: *** "Can't find /usr/src/linux-headers-4.4.0-51-generic/include/linux/version.h".  Stop.
make[3]: warning: jobserver unavailable: using -j1.  Add `+' to parent make rule.
ret=$?
kill %%
exit $ret