Each snippet of console output is stored in a separate file in the job result
directory. Collect these tiny files into module result JSON files at the end
of each job. This can speed up server-side job details JSON generation up to
5 times when the disk cache is empty.

…ils loading

* Remove $collect_text flag and instead cover that case within tests
* Handle errors when reading the text file
* Improve coding style

* Test error cases as well
* Check the minion job state

…n finalized