Allow for primary log rotation by copy and truncate rather than rename

I found that Yii rotates files by renaming them and creating a new primary log file when necessary. This poses a problem for any tailing programs which rely on the inode staying constant. I found Paper Trail's remote_syslog (https://github.com/papertrail/remote_syslog) to be one such program.

With this commit, I added the boolean option "rotateByCopy" to CFileLogRoute.php to allow the user to request that the primary log file(s) be rotate by "copy and truncate" rather than "rename".