Make rviz default orientation match gazebo

[PaulBouchier]

I don't know if this is the best way to fix issue #179 but it's a way. If it's confusing for me, and I've been working with linorobot2 for a while, it will be doubly confusing for newcomers to figure out what the correct initial 2D pose is, considering that the general form of the gazebo model and the map are rotationally so symmetric. By default, the system should (IMHO) come up in a ready-to-use state, and this change makes it so.

A related PR in linorobot2_viz does the same thing as this PR: changes the default view in rviz.

[grassjelly]

Thanks for the PR @PaulBouchier. I see a lot of good stuff included in this PR (7 changes in total). Could we keep the changes minimal and only keep the ones related to getting the orientation right in the RVIZ config?

[PaulBouchier]

@grassjelly I may be using github incorrectly, but I submitted 3 separate PRs, each with their own branch, because each deals with a different issue. However, each branch was branched off the previous one, and github seems to have aggregated them. Maybe I needed to branch each off a common point.

The most important PR is PR #178, which makes docker work.
The next most important is PR #177 which gets rid of a warning
The 3rd one is PR #180 which is a save of the rviz config, and rviz always changes lots of things when you save, even if all you did was rotate the view (which is what I did).

Please advise if I should do things differently.

[grassjelly]

that makes sense. Sorry missed the other PRs

[PaulBouchier]

Next time, I'll base the branches off a common base point. I didn't realize that would be important. Note that there is also a PR for linorobot_viz, dealing with rviz orientation. Thanks!

[grassjelly]

@PaulBouchier please rebase this too. Thanks

[PaulBouchier]

Done. Thanks for the merges!