Added mlock and munlock functions on std::strings
Added missing documentation for unboxer::get_nonce_constant
Made static linking with libsodium work, used CMake Debug/Release
system.
Added Vim swap files to gitignore
Fixed initialization of overflow in nonce and usage of "=" instead of
"==" in  operator==.
eliminating compiler errors caused by using user-defined type names as identifiers, and missing includes