Enhancement: Added file type icons next to project documents and bug file attachments. Also provided a set of
standard icons. More or better icons are welcome!

M config_defaults_inc.php

• New config option (file_type_icons): provides mapping between file extensions and icons to be used for file
  types.

M core/print_api.php

• (print_file_icon): Prints the icon corresponding to the specified filename.

M core/file_api.php

• (file_get_extension): Extracts the file extension given the filename.
• (file_list_attachments): Now prints file type icons next to attached files.

M proj_doc_page.php

• Now prints file type icons next to project documents.

M doc/ChangeLog

• Updated the change log.

A images/excel2icon.gif
A images/fileicon.gif
A images/gificon.gif
A images/htmlicon.gif
A images/jpgicon.gif
A images/mailicon.gif
A images/pdf2icon.gif
A images/pdficon.gif
A images/pngicon.gif
A images/ppticon.gif
A images/texticon.gif
A images/unknownicon.gif
A images/word2icon.gif
A images/zipicon.gif

• Added some more standard document file type icons.

git-svn-id: http://mantisbt.svn.sourceforge.net/svnroot/mantisbt/trunk@1996 <a class="text" href="/?p=mantisbt.git;a=object;h=f5dc347c">f5dc347c</a>-c33d-0410-90a0-b07cc1902cb9