Adding links to new 1.4 doxygen documentation (temporary url).

git-svn-id: svn://svn.code.sf.net/p/stxxl/code/trunk@3230 4e380d45-d1fd-0310-85a7-d18ec86df0ad
Removing 1.3.0 references, adding github and rewriting people names.

git-svn-id: svn://svn.code.sf.net/p/stxxl/code/trunk@3231 4e380d45-d1fd-0310-85a7-d18ec86df0ad