Don't use unix specific compiler option on windows
Merge pull request #177 from leapmotion/fix-winbuildwarning

Don't use unix specific compiler option on windows
Need to specify dllimport/dllexport in order to create an import lib on Windows
Merge pull request #178 from leapmotion/fix-dllimport

Need to specify dllimport/dllexport in order to create an import lib on Windows
Merge remote-tracking branch 'origin/develop'