PLN won't compile with gcc-4.7

So just stub it out ... it is unused, unmaintained, and it is in the
process of being replaced by a python implementation.
Uncomment debug printfs in MathUTest
Make a weak stab at fixing MathUTest
Merge pull request #308 from linas/build-fixes

Make a stab at fixing MathUTett
Add libserver.so to CMakeLists.txt cogserver_cython to fix #307 & #305 as suggested by IvanLim
Merge pull request #310 from cosmoharrigan/CythonTest

Add libserver.so to CMakeLists.txt cogserver_cython to fix #307 & #305 a...
Merge branch 'master' of github.com:opencog/opencog