TagLibAmalgam: A new way to use TagLib

[Vinnie Falco]

Alright, I've included all the public headers (according to the
CMakeLists.txt entry). Furthermore, I have cut down the size of the
resulting amalgamation significantly by not repeating header
information. This is done with the "@remap" metacomment in the
template.

You can try the new amalgamation in the 'develop' branch of TagLibAmalgam:

https://github.com/vinniefalco/TagLibAmalgam/tree/develop

If you're happy with these changes then after the fixes for warnings
are merged in the official repository, I will update all of my
repositories fully (the tool, the template, and the amalgamation).