tigefa4u projects Trac

Need to tell FieldStorage to keep blank values to fix #785.

Scroll code blocks horizontally if necessary

Make the links to modified files in the changeset overview jump to the corresponding diff. Make the file path and the revision numbers in the diffs link to the corresponding version of the file in the browser.

* Cleanup the Wiki template and the related JavaScript functions for saving/restoring the state of the textarea for previews
* Make highlighting of rows in the query results table consistent with other tables in Trac
* Make the summary column in query results links to the corresponding tickets
* Fix the links of the summary column in reports so that they actually link to the corresponding tickets
* Remove executable bit from {{{trac.js}}}

Make complete cell clickable in the statistics table of the milestone view.

Make report display more consistent with other tables in Trac. Link summaries to ticket. Fixes #306.

Make the highlighting of changes within lines off diff coarser-grained for better readability. Fixes #434.

Applied fixes to wiki error messages and ticket previewing contributed by Christian Boos. Thanks a lot\!

Added more TracAdmin tests contributed by Tim Moloney. Thanks\!

Fix #764