Implement 0002067: The option to display "project name : category name"
rather than "category name" only in call "All Projects" is selected. This can
be enabled or disabled via $g_summary_product_colon_category which is
disabled by default for backward compatability.

git-svn-id: http://mantisbt.svn.sourceforge.net/svnroot/mantisbt/trunk@1052 <a class="text" href="/?p=mantisbt.git;a=object;h=f5dc347c">f5dc347c</a>-c33d-0410-90a0-b07cc1902cb9