Add administrative files

[cvvergara]

@iboates We are making all the repos to have the following files: https://github.com/pgRouting/pgrouting/blob/master/LICENSE https://github.com/pgRouting/pgrouting/blob/master/CONTRIBUTING.md https://github.com/pgRouting/pgrouting/blob/master/CODE_OF_CONDUCT.md

This one can be different. Because we haven't set up a coding convention well its up to you now Later we can decide. https://github.com/pgRouting/pgRoutingLayer/blob/master/CONTRIBUTING.md

BTW do you know how to add a license in a python file? I tried something like this: https://github.com/pgRouting/pgrouting/blob/master/src/dijkstra/dijkstra.c But it gets as part of the description when I use help(module)

[iboates]

Just acknowledging that I have seen this. I recently arrived back home from holiday.

[iboates]

https://github.com/pgRouting/osm2pgrouting4qgis/commit/79ce34b0749a7564b4598a2079f86aee6d65d444