Added a configuration option to reverse the sorting direction of the edges (neighbours).
For edge sorting, reduced the code to choose between directions.
Merge pull request #14 from ScottSallinen/edgelist-ordering

Implemented an option to choose direction of Edge-list ordering.
Fixed a bug for edgelist ordering to allow default calls to the sorting neighbours function.
Updated the top-level makefile with an explicit all rule that compiles all possible binaries.
Merge pull request #15 from ScottSallinen/edgelist-ordering

Fixed a bug for edgelist ordering to allow default calls to the sorting neighbours function.
Merge pull request #16 from ahgharaibeh/compile-all

Updated the top-level makefile with an explicit all rule that compiles all possible binaries.