Yaml cpp update to 0.3

*update yaml-cpp to latest (but older) API 0.3 
*also remove the sources for the library and just provide the linked lib (like with others)

This would need libyaml.a rebuilt for other platforms (darwin64, arm7,win32): 
please
1/ download http://code.google.com/p/yaml-cpp/downloads/detail?name=yaml-cpp-0.3.0.tar.gz
2/ extract
3/ change line in CMakeLists.txt from         set(GCC_EXTRA_OPTIONS "")
 to         set(GCC_EXTRA_OPTIONS "-fPIC")
4/ mkdir build && cd build
5/ cmake ..
6/ make
7/ copy libyaml.a to external/{platform}/

thankyou!