Fixing file path
copy required dep to output folder
fixes #4 including dllmap fix mono tests for osx

The following changes address the problem of the tests not being able to
find the compiled libsodium.dylib.

For mono running x86, libsodium.dylib needs to be arch i386

All tests passes
Merge pull request #12 from fraga/fixSolution

Fix solution, correcting tests for OSX