Rebase iso to Lubuntu 18.04.2

[kalxas]

​https://github.com/OSGeo/OSGeoLive/pull/222

[darkblueb]

12dev build285-master

lsb-release shows DISTRIB_DESCRIPTION="Ubuntu 18.04.1 LTS"

[kalxas]

we still use the 18.04 iso

[kalxas]

I have been trying to get 18.04.2 iso to work with our build process.

Unfortunately there is a major change in the Ubuntu iso since 18.04.1 that breaks our process:

Debian and subsequently Ubuntu has moved to multipart initrd files for the live-boot system.

This means that the initrd.lz file we used to create in bin/build_chroot.sh is now invalid and will cause a kernel panic during boot (see screenshot in ​https://github.com/OSGeo/OSGeoLive/pull/222).

• ​https://wiki.ubuntu.com/BionicBeaver/ReleaseNotes/ChangeSummary/18.04.1
• ​https://bugs.launchpad.net/ubuntu/+source/live-build/+bug/1778811
• ​https://wiki.debian.org/initramfs#How_to_inspect_initramfs
• ​https://unix.stackexchange.com/questions/163346/why-is-it-that-my-initrd-only-has-one-directory-namely-kernel
• ​https://askubuntu.com/questions/1094854/how-to-modify-initrd-initial-ramdisk-of-ubuntu-18-10-cosmic-cuttlefish
• ​https://askubuntu.com/questions/777260/how-to-repack-initrd-img

I am working on a solution for this, more details to follow.

[kalxas]

Solution committed:

​https://github.com/OSGeo/OSGeoLive/pull/251/commits/c484c72f43bc8e4bf51e369ccd005b75047dce16

[kalxas]

Fix confirmed.