tigefa4u projects Trac

Try to fix the display of diffs in Konqueror, as suggested by trac@... Fixes #1246.

If unspecified in TracIni, the width and height of the logo won't be specified in the <img> tag either. Fixes #2767.

Also show diffs for files edited after a copy or a rename operation. Fixes #3172.

setuptools branch: move templates into subirectories of the subsystem they belong to.

setuptools branch: remove some unused files / code.

TracChangeset view now takes the `FILE_VIEW` and `BROWSER_VIEW` permissions into account.

* FILE_VIEW is required to be able to view the diffs (be it in the HTML view, or as a plain diff or zip archive)
* BROWSER_VIEW is required to be able to see the file or directory paths that have changed

Fixes #2268.

setuptools branch: moved default wiki pages and macros into package data. In addition, they are now installed by the `WikiSystem` component by implementing `IEnvironmentSetupParticipant`.

Some wiki formatter cleanup, in follow-up to r3376 and r3377:
* removed the special handling done for MoinMoin `["internal free link"]`
syntax introduced in r3295, as this now also works thanks to r3376
* fix the relative link syntax broken by r3376, i.e. things like:
* `[/download Download area]` ''link relative to the server's root URI
* `[../other see other]` ''link relative to the current location''
* fix some macro calls counter examples
* added a regression test for #3245

setuptools branch: starting the required changes.

Init sandbox branch for setuptools adoption as proposed in trac-dev:590.