Log Message:
Update to 1.5.2 to fix build with gcc4 on 3.99.21. Ok agc@

Changes in OpenSP 1.5.2

* Support for version 4.0 and 4.1 of the GNU C++ compiler.
* Added doc building and config option.
* Updated local gettext.
* Added config option to turn off DTDDECL support.
* Update 'de' and 'fr' translations; add new 'tr' translation.
* Add more tests. (Karl Eichwalder)