Do not use the TQL DB when the matching is done on the "a" tag.

This new feature is not yet implemented in cc-node.

This reverts commit 8bc10912.

We used to wait the end of the export_volume job before doing anything
else. Now, we have a timeout waiting inside a loop, so we can update the
job status by getting information from the node.

This patch comes with the commit named 'Handler to get data from the
child of a ForkedJob' in cc-node which implements the handler needed
to get the information from the job.

This patch adds a handler for the helpplugin command.

This patch comes with a patch for cc-cli and a patch for cc-node.