Feature: Add support for more fields, allow branch+commit+tag, fix error output

[henrygrant]

Adds some additional parameters you can feed to the Bitrise API. These were necessary for more context in our Bitrise builds, and enabling auto-aborting of repeated builds to branches with open PRs.

I also removed the guard that requires only one of [branch|tag|commit] as params. Even though the documentation indicates you are only supposed to have one of these, the commit information still gets populated when you push a value for -b and -c.

This was an issue for my team, as we moved from webhooks to using Gitrise, but upon doing so and passing -b for the branch name, we lost commit context. This got it back for us.

Also, it seems like bitrise changed the key of the error message in the response object from message to error_msg. Addressed in this MR.

[henrygrant]

Curious about what anyone else thinks about the non-mutual-exclucivity of tag, commit, and branch