Add offered qos incompatible event and event executor test

[ivanpauno]

(edit) #10 has already been merged.

This PR is build on top of #10.

It adds a new publisher event status: OfferedQosIncompatible.
That new event status is used to test the executor code in #10, which surprisingly works without changes.

There are some other cosmetic changes here.

I will rebase and redirect the PR to feature/events when #10 gets merged.

[jacobperron]

surprisingly works without changes.

😂

[jacobperron]

Besides the minor comments above, this LGTM

[ivanpauno]

I have rebased feature/events against foxy-devel, and this branch against feature/events.
In that way, we can see CI being exercised now 😃 .

[ivanpauno]

@jacobperron there are some event statuses that we want but are not available in foxy (e.g. message lost), should we create a galactic-devel branch?

(edit) that should be done after completing basic event handling support in the foxy branch

[ivanpauno]

Unrelated, but I want to get rid of all stale branches.
Do we need to keep some of them or can I delete them all?

[jacobperron]

@ivanpauno

there are some event statuses that we want but are not available in foxy (e.g. message lost), should we create a galactic-devel branch?

Yeah, feel free to create a galatic-devel branch when the time is right.

Unrelated, but I want to get rid of all stale branches.

Go ahead and delete stale branches 👍