bundled saxon considered harmful

Hi all,

we are currently shipping two transformers for XSLT import/export
filters. The default one is libxslt-based (thanks, Peter!) and is used
for all our internal filters. The older saxon-based one only remains as
a backup, in case some existing filter needs features not-supported by
libxslt (e.g., XSLT 2.0[1]). It has always bothered me (and other
package maintainers too) that we have to bundle saxon*[2] just because
of something that is most probably never used.

I propose that we change the saxon-based transformer into an extension
and then drop it from our codebase. The first step has already been done
on branch feature/kill-saxon. The other step requires to answer the
question "where to put it?" There are two possibilities:

1. a repo on fd.o under libreoffice
PROS:
* probably easier to setup
* automatic commit rights for everyone with commit rights to libreoffice
CONS:
* it is somehow tied with libreoffice, so people might expect us to put
  the extension into the install sets (which is what I wanted to avoid in
  the first place :-)
* it would set a precedent. Authors of other extensions might expect us
  to set up a repo for them too....

2. a repo on github or similar
PROS:
* distance from libreoffice. It is not part of our project, so we are not
  obliged in any way to ship it :-)
CONS:
* no automatic commit rights (but who would want to commit to the
  project anyway? :-)

This also needs license cleanup first, as the related files are still
under the old LGPL3 license.

To summarize what needs to be done:
1. select a new home for the code
2. clean up the license
3. write a makefile (or build.xml) to build it outside of libreoffice
   build system
4. move the code over to the new place and drop it from core
5. live happily ever after

Opinions? Objections?

[1] Support for XSLT 2.0 was one of the reasons for switching to saxon
in OOo 3.2 (or was it 3.1 already?), as there were demands for it. I do
not know of any such filter, though.

[2] Saxon comes in several variants and the open source one, found in
Linux distributions, is lacking a lot of features.

D.