Update CMakeLists.txt

add SAFESEH:NO when build use vs2012 win32
Update vrpn_Shared.h

fix vrpn_float64 htond( vrpn_float64 d ) override winsock.h htnod only with return type when build with vs2012 win32
Update ocachesrv.cpp

fix implicit conversion to explicit conversion when convert from Setting to String
Merge pull request #14 from sufulow/master

build with vs2012 win32