(travis) Install older DBD::SQLite on perl < 5.8.4, I fucked up on testing

Related RT: https://rt.cpan.org/Ticket/Display.html?id=99747
ribasushi--
(travis) Feeble attempt at reverting f207111d

The toolchain gang became *a little* more reasonable in the past year, let's
see how far we get without this particular set of workarounds
(travis) Reshuffle CI workflow, prepare for better instrumentation of failures

No functional changes at this point, the goal was to have no exports in
30_before_script.bash and 40_script.bash, allowing me to run everything
after 20_install.bash in a subshell
(travis) Better diagnostics on *why* a build failed

Especially useful when travis wakes up the OOMKiller

As a bonus add getstatus to all subshells for better idea wtf just went wrong
(travis) Add 5.8.4 testperl and also make the travis 5.8 run first

Will give a much faster reponse time if something 5.8 related fails