C++ only works when installed from repo not from release

[erksch]

Hey there!

Trying to get this lib to work for C++ was giving me headaches until I discovered this pull request (Add support against linkage with C++ programs ), and your comment that you added the support with this commit.

I downloaded the lib from the release page which is quite outdated and this fix was not included in that release. Cloning and building solved my problem and the header then included the code I needed.

So either advise people to build directly from master or make a new release.

Many thanks :)