remove author headers from source files

[bbortt]

these comments are obsolet on the class level:

/**
 * @author xy
 */

git history already provides this information.

acceptance criteria: remove the @author comments from the top of all source files.

[ueberfuhr]

Seems to be common sense, but not yet common everywhere. Spring still uses @author tags. Gradle doesn't.

[bbortt]

thanks for the addition. it is also common sense to us (@christophd & me) 😉