instance/pyros-setup.cfg in source useless and confusing ?

[asmodehn]

instance/pyros-setup.cfg came from a time when pyros-setup was used from ROS, and could be used from a workspace. But these days pyros-setup is only needed from a python virtualenv, so there is probably no point having this file there ?
And maybe worse, the behavior of getting config from a source folder, and packages from that workspace,even though we are using a venv, is confusing ?

[asmodehn]

It seems this file is completely unneeded any longer.

Even if we happen to have pyros_setup in a source workspace, it is not a catkin package, so it wont be picked up by our code. The code will directly go invoke the pyros setup installed in the environment (system in ROS workspace case), and the pyros-setup.cfg is useful only when run from source.

Since pyros-setup is an import util, it is not run directly from source, but should instead be installe dint he environment... and it is simpler to not get confused in all this import logic, if we directly do a full install (no develop, .pth trick, etc.)

=> lets get rid of instance/pyros-setup.cfg

[asmodehn]

In progress in #40