testbench: add mysql tests

but do not yet activate them
bugfix: output modules with parameters with multiple passing modes could cause strange behaviour including aborts

This was due to the fact that the action module only preserved and
processed the last set passing mode. Note that this was not a problem
for the plugins provided by the rsyslog git: none of them uses different
passing modes.
Thanks to Tomas Heinrich for providing a very detailled bug report.
bugfix: mishandling of input modules not supporting new input instances

If they did not support this, accidently the output module part of the
module union was written, leading to unpredictable results. Note: all
core modules do support this interface, but some contributed or very
old ones do not.
bugfix: double-free when ruleset() parser parameters were used

While unlikely, this could cause stability issues even after the
config phase.
Merge branch 'v7-stable-act-tpl-passing-mode' into v7-stable

Conflicts:
	ChangeLog
fix small memleak in action()

This was introduced by a recent patch. Not present in any
released version.
bugfix: remove duplicate code
bugfix: don't export uninitialized data
bugfix: correct variable mismatch
bugfix: add a missing flag and prevent memleak
Set default value of eParamPassing explicitly
bugfix: allocate correct object type
Use uchar instead of char for type size reference
bugfix: prevent passing NULL to strstr, strlen
bugfix: prevent division by zero

The result is set to 0 in that case. Might be better to do something
else in the future, but at least it'll stop crashing for now.
bugfix: relax a too strict condition
unpick commit 5c4cb78ac15e841726af672a8a227017a2516cfa

The variable initialized there was removed by my larger patch
a couple of days ago. Accidently cherry-picked that commit.
maintain ChangeLog
fix inconsistent write/deref in action config processing

Thanks to Tomas Heinrich for alerting us.
Merge branch 'v7-stable' of git+ssh://git.adiscon.com/git/rsyslog into v7-stable