Add missing property declaration.

It was making PHPStorm unhappy :(
Remove conditional emty arrays in selectActionableStreams

Neither readStreams or writeStreams are ever completely unset and the calling method checks that at least one of them has some sort of contents. There is no need to check if one is an empty array, and if so, supply an empty array.
Checking one array, but using another
Improve timeout calculation.

Remove string processing in favour of maths.
Move sec/usec calculation inside condition so they're not calculated when not needed.
Removed unnecessary intermediary garbage storage
Merge branch 'assorted_tweaks' of git://github.com/leight/Alert into leight-assorted_tweaks