0.1.5    31.10.2014
           - require perl 5.18.0 (earlier perls dont have required API)
           - added shared_ptr, Refcounted and docs
           - added typemaps for panda::shared_ptr and std::shared_ptr + tests
           - refactored all typemaps
0.1.4    10.10.2014
           - added hv_fetchhek, hv_storehek, hv_deletehek
0.1.3    10.10.2014
           - allow only RV to undef for obj2hv/obj2av, as perls < 5.20 don't allow to upgrade strings
0.1.2    09.10.2014
           - added support for HV* CLASS in object constructors (output typemaps)
0.1.1    08.10.2014
           - docs fixes
0.1.0    04.10.2014
           - first release