new kernels available

Latest secure kernels available in the repos for 32 and 64 bit architecture (stretch, buster, testing and sid).

5.2.15 (64bit and 32 bit pae and non-pae-486)
4.19.73 (64bit and 32 bit pae and non-pae-486)
4.9.193 (64 bit and 32 bit pae and non-pae-486)

Users are strongly advised to upgrade.