This commit includes two related fixes:

• Fix 0002075: Mantis does not correctly display images when they are clicked ( $g_file_upload_method = DATABASE
  ).
• Fix 0002940: Error when uploading document with no upload path.

M bug_file_add.php

• Moved the checking of the upload path to file_add() in file_api.php

M proj_doc_add.php

• Added checking for the upload path (not empty, exists, writable, and directory)

M core/file_api.php

• (file_add):
  • Fixed a bug where filesize was equal to 0. This caused files not to be uploaded to DATABASE.
  • Some readability changes.
  • Added checking for the upload path (not empty, exists, writable, and directory)
• (file_ensure_valid_upload_path)
  • Changed to reject empty paths.

M core/project_api.php

• (project_create): Send path for validation only if not empty.
• (project_update): Send path for validation only if not empty.

git-svn-id: http://mantisbt.svn.sourceforge.net/svnroot/mantisbt/trunk@2042 <a class="text" href="/?p=mantisbt.git;a=object;h=f5dc347c">f5dc347c</a>-c33d-0410-90a0-b07cc1902cb9