Revert "adds libdivsufsort dir to includes for the unit tests"

This reverts commit 3f7a6cf64c8565e5f5c4e21448e739b021babb22.
replaces auto with proper types to support older compilers
Merge branch 'master' of https://github.com/kloetzl/andi
first take at another optimization
Merge remote-tracking branch 'origin' into ubuntu