Added openssl patch for fedora 20

This is a patch that has to be applied when you want to use Execoin Wallet on Fedora 20 as Openssl isn't available at same place as in ubuntu/debian.

You also have to remove de -mingw references in the makefile. (I didn't include it in this merge request. Could open an other one for it).

With those 2 things, the wallet compiles great !