Update Readme that we are not using Google style

[AndyZe]

No description provided.

[nbbrooks]

If this is the case, I don't understand why this PR is failing the clang job

[nbbrooks]

This is failing clang because the "ERROR_CODE_MAP" is formatted nicely, but not according to clang. I'd just block it with
// clang-format off
...
// clang-format on

edit: Oh yeah...ctdc doesn't make this modification so I wanted to figure out why CI was modifying it

[zultron]

The CI failures where clang-format broke up strings in that nasty way (unfold the "Running clang-format" part of the log), I fixed in commit e12fb23 over in #63. I also put in a PR over at PickNikRobotics/roscpp_code_format#14 so this problem doesn't propagate further.

[AndyZe]

This is outdated since we use pre-commit for formatting