Add \EHsc flag for MSVC
Add \EHsc flag for MSVC

MSVC doesn't like compiling boost stuff without it.

qwerty01/Client,HorizonLauncher/Client,Proj-Ascension/Client,Hal9007/Client,HorizonLauncher/Client,swordworld/Client,elken/Client,swordworld/Client,elken/Client,3mRe/Client,3mRe/Client,Proj-Ascension/Client,Orochimarufan/ProjectAscensionClient,lolzballs/Client,qwerty01/Client,Orochimarufan/ProjectAscensionClient,lolzballs/Client,Tom-Todd/Client,Hal9007/Client,Tom-Todd/Client