[FIX] remove debug code
[FEAT] pool hosts

A pool host is a host entry that refers to more than one actual
machine. Therefore, the pool host has a count associated. Every time a
job is scheduled on the pool host (i.e. mark_job_as_running with
$job->host is pool host) the pool count of the host is reduced. Only if
the pool count reaches 0 the pool host becomes nonfree.

Note: There is no mechanism to keep an original pool count. When you
stop jobs without using mark_job_as_finished the count will most
certainly be incorrect.
[TEST] for pool hosts
testrundb.version++
enhance pool hosts

When a pool host is scheduled some part of the MCP (e.g. producer,
resetter) may replace the host entry in the testrun_scheduling returned
by scheduler. We don't want to loose the pool association on the
replacement host and therefore need a connection back to the original
pool host. This patch provides this-
Update method documentation
Add setter functionality to pool_count

pool_count used to be a getter for the sum of used and unused elements
of a pool host.
It's obviously also necessary to update this value. Therefore, I added
setter functionality to this function. Since there is no field for the
sum, this works by calculating the number of used pool elements,
substracting it from the requested number and putting the result in as
new pool_free.
Added comment

Clarify why we do pool operations when host is not a pool host and we
get a new pool count - in this case the host becomes a pool host.
[FIX] changing pool count of host

When a non-pool host becomes a pool host or a pool host gets a bigger
pool count, it has to be set as free. Previously, it was set to active.
[FIX] updating pool hosts for marking jobs as running and finished

When a job is marked as running of finished, its associated host needs
to be updated. For pool hosts, this means the pool_free counter needs to
be updated. To make this update correctly, we need to reread the current
value from the database into the DBIC object and then execute the update
in a transaction.
[FEAT] added options and name to scenario table
added distupgrade files

Includes distupgrade files for TestrunDB, versions 4.001004 to 4.001007.
[FEAT] allow setting status of new testruns

Before all new testruns got the status "schedule". This makes it
extremly hard to add multiple interdependend testruns atomically. Now we
can overwrite the status ('prepare' makes sense).
[FIX] add moreinfo-url to recognized metainfo tags
[FIX] peers_need_fitting only for interdep scenarios

Whether peers need fitting is only relevant for interdep
scenarios. Therefore, the function that counts them should
check the scenario type and return 0 for non-interdep.
[FIX] host_free on finished testrun for pool hosts

A pool host can have a pool_free below zero when the user reduced
the pool_count below the number of currently used pool elements. In this
case, when a testrun on one of the pool elements is finished, we can not
always set the pool host to free. Instead, we need to check whether
pool_free is above zero.
Merge /home/local/ANT/caldrin/Projekte/Tapper/src/Tapper-Schema