Those are directed graph with arrow saying that
originated library dependes on target library.
Dependance mean here a header inclusion from dependant
library in the current library.

Ext_dependence.dot
==================
dependancy of xFiles libraries against external
libraries. May not be exhaustive.

Xfiles_dependence.dot
==================
dependancy of xFiles libraries
May not be exhaustive.
 blue connection are comming from recent move from
 xFEM to xExport and xLegacySimpleCut. Maybe in
 future we wil remove them
 red connection commes from CMAKE and shoud not exist

To generate png images
======================
dot -Tpng -o Xfiles_dependence.png  Xfiles_dependence.dot
dot -Tpng -o Ext_dependence.png  Ext_dependence.dot