Admin/components/main

use polyml-test-0a6ebca445fc by default: already quite stable;

#main components for everyday use, without big impact on overall build time
bash_process-1.2.2
bib2xhtml-20171221
csdp-6.x
cvc4-1.5-4
e-2.0-2
isabelle_fonts-20181129
jdk-11+28
jedit_build-20190120
jfreechart-1.5.0
jortho-1.0-2
kodkodi-1.5.2-1
nunchaku-0.5
opam-1.2.2
polyml-test-0a6ebca445fc
postgresql-42.2.5
scala-2.12.8
smbc-0.4.1
spass-3.8ds-1
sqlite-jdbc-3.23.1
ssh-java-20161009
stack-1.9.3
vampire-4.2.2
xz-java-1.8
z3-4.4.0pre-2