Errors in log file when viewing an institution or site html file

[Son Nguyen]

Version: master
Platform: all
Browser: FF

Steps to produce the issue:

1. Login as an institution admin or site admin
2. Upload an institution and/or site HTML file
3. Access institution or site files (/artefact/file/institutionfiles.php or /artefact/file/sitefiles.php)
4. Click on the file name to view
5. Check the log file, you have these errors:

[Tue Feb 12 15:49:17 2013] [error] [client 127.0.0.1] File does not exist: /home/sonn/code/mahara/htdocs/sites, referer: http://mahara/artefact/file/download.php?file=139
[Tue Feb 12 15:49:17 2013] [error] [client 127.0.0.1] File does not exist: /home/sonn/code/mahara/htdocs/sites, referer: http://mahara/artefact/file/download.php?file=139
[Tue Feb 12 15:49:17 2013] [error] [client 127.0.0.1] File does not exist: /home/sonn/code/mahara/htdocs/sites, referer: http://mahara/artefact/file/download.php?file=139
[Tue Feb 12 15:49:17 2013] [error] [client 127.0.0.1] File does not exist: /home/sonn/code/mahara/htdocs/sites, referer: http://mahara/artefact/file/download.php?file=139
[Tue Feb 12 15:49:17 2013] [error] [client 127.0.0.1] File does not exist: /home/sonn/code/mahara/htdocs/sites, referer: http://mahara/artefact/file/download.php?file=139

However, you still see the content of the HTML file and continue without problems