[libvoikko] Adjustments to licensing policy (GPL versions)

[Harri Pitkänen]

I noticed today that the license of Autoconf (including Autoconf macro 
archive) has changed to GPLv3+. In fact one newly introduced file in upcoming 
libvoikko 3.0 (m4/acx_pthread.m4) is under the new version of the license.

When interpreted strictly our current policy for licensing of libvoikko would 
not allow us to include such file since we require compatibility with GPLv2. 
We can't stop using Autoconf and I don't see any reason to do so since we 
don't need to use GPLv2 for our build system.

Thus I propose that we modify our current policy ( 
http://voikko.sourceforge.net/contributing.html ) so that instead of 
requiring the whole libvoikko subdirectory to be under GPLv2+ we only require 
that license for subdirectories libvoikko/data, libvoikko/python and 
libvoikko/src. This allows using the library in GPLv2 applications but won't 
stop us from using the later version for tests and build system code.

I think that the GPLv2 requirement can also be removed from trunk/debian, 
trunk/docs and trunk/tests.

Unless I hear objections I make these changes before the release of libvoikko 
3.0.

Harri