[reSIProcate] file-based logging max line count

[Jason Fischl]

I've added a mechanism into resip file-based Logger to allow a maximum
log-file size. By default, this new feature is turned off. If you want to
turn it on,

GenericLogImpl::MaxLineCount = 5000;

If you set this before you start using the logger, the file will be reset
when 5000 lines have been written. I realize that this isn't ideal, but it
stops the log file from just growing continuously. At some point, it would
be great if somebody could set it up to roll the log files over to a
configurable maximum.

Jason