Succesfully compiled IceCat using devuan

[Jens Korte]

Hi

I compiled IceCat 68.4.1esr (64bit) using Devuan. This is a short
summary what I did:

* cloned with git https://gitlab.com/anto.trande/icecat/
* in makeicecat I replaced the prename lines with lines from gnuzilla
  since devuan doesn't provide prename
* cd icecat-68.4.1/python/mozbuild/mozbuild/test/action; ln -s
  test_package_icecatmobile_apk.py test_package_fennec_apk.py #
  configure wants another filename, I guess because of the other rename
  commands
* mkdir obj; cd obj; ../configure # I used --with-ccache
* several packages were missing for configure and make. at least:
  cargo, clang, clang-lib (?), libdbus-glib-1-dev, libxt-dev, nasm,
  yasm 


When trying to compile icecat for the first time, my PC wasn't reacting
anymore. I changed the btrfs filesystem with compression to btrfs
w/o compression and w/o cow. I limited the count of make jobs to 1.

time nice -n19 ionice -c3 make -j 1

Jens