Add 'make install' functionality

[Theo Steininger]

It would be nice to make hamx fully installable including a install prefix.

[Gioacchino Wang]

could be better if we write a cmakelist or an autoconfig file once for all?

[Gioacchino Wang]

Hi Theo,

Last time I didn't fully catch what you mentioned, now I've rewritten the makefile which includes installation feature, please check the "unitest" branch (which will be merged, with other updates, to master when you finish editing your paper).

Thanks!