Fix for failed Chocolatey Installs on .net 2/3.5 clients as of 3/19/14

Without this fix, due to a change on Github;s end, Chocolatey installations fail on all .net 2/3.5 clients

the Github Raw endpoint does not honor TLS and the .net 2.0 client will not fall back to Ssl3 un like the newer .net4 clients. So .net2 will time out if we do not explicitly set the protocol to Ssl3