Okay, now it works:
I have done it that way:
1. I removed the maven-dependency-management of the project.
2. I removed the JSF-Capabilities of the project.
3. Then, I added maven-dependency-management of the project again.
4. And after all, I added the JSF-Capabilities of the project again.
And now all files are hot-deployed (automatically).
Besides, sporadically the jsf-capabilites are removed from the project without my will. I do not know why. Maybe Maven overwrites some project-settings which are needed by jsf-tools.