Enhance tests

[liquidnya]

Minor improvements to the test case source code.
This will allow to have test cases that have a log of more than 1 day (e.g. 3 days)
and also fixes some issues concerning time emulation as well as some issues with the emulated file system when testing a restart ("emulated crash") of the queue.

[liquidnya]

I also added some very basic and specific tests for weighted random.
Notably one of them (weight-remove.test.log) tests that the weighted random time is not removed from an incorrect user:
3f220f5#diff-f5ae652c672a0eb5c4e9845223e9f5ad1ae53526047dd1460e98bcd8717a4b56R46

In the other test case (weight-crash.test.log) a bug scenario is shown:
When the queue crashes after a wait time was changed (because someones level got picked) and before the 1 minute timer writes the new files to disk, then the wait time will be the previous one.
Even though this bug is shown, I suggest not fixing it, due to 3 reasons:

• It is a very rare condition
• In case it happens, it is in favor of the person who it happened to
• Even if the wait time would be persisted whenever someone is removed from it's list,
  then the window of data being corrupt just gets smaller and does not fix the underlying issue

So I would suggest to eventually fix the underlying issue and to ignore those rare edge cases for now.

[ToransuShoujo]

https://stackoverflow.com/questions/7957544/how-to-ensure-that-data-doesnt-get-corrupted-when-saving-to-file/7957634#7957634

Thinking of resolving like the top comment here does.

[liquidnya]

I've created the issue #12 for the underlying issue.