$Time/$number stream matching, add separators

[RufaelDev]

To map segments back to their cmaf tracks, it would be good to add that
$Representation$ substring shall occur before $Time$ or $Number$ and that $Time$ , $Number$ shall be separated by a non number separator character. This avoids cases like $Representation$122324$Time$232 when distinguishing the time would not be possible, instead $Representation$122324-$Time$-232 would work