Continue merge after conflict solving

When merging a conflict may occur. The repository is now in a merge state, where a user has different options:

• abort the merge
• solve conflicts and continue

While rebase has a "continue" button, merge has non. Users have to know, that the "continue" button is equal to the "commit" button.

The latest version 19.1 RC2 shows a nice bar:

I suggest:

1. Rename "Commit" to "Continue" in that state.
2. Add a continue button close to the "Abort" button in the merging-state bar.

Thanks,

    Patrick