tree-wide: drop maintainership

Maintainer confirmed via E-Mail exchange that maintainership is to be
dropped

community/docker-registry/APKBUILD

-# Maintainer: Christian Kampka <christian@kampka.net>
-
+# Contributor: Christian Kampka <christian@kampka.net>
+# Maintainer:
 pkgname=docker-registry
 pkgver=2.7.1
-pkgrel=2
+pkgrel=3
 pkgdesc="An implementation of the Docker Registry HTTP API V2 for use with docker 1.6+"
 url="https://github.com/docker/distribution"
 arch="all !s390x !mips !mips64"

community/torsocks/APKBUILD

-# Maintainer: Christian Kampka <christian@kampka.net>
+# Contributor: Christian Kampka <christian@kampka.net>
+# Maintainer:
 pkgname=torsocks
 pkgver=2.3.0
-pkgrel=0
+pkgrel=1
 pkgdesc="Wrapper to safely torify applications"
 url="https://gitweb.torproject.org/torsocks.git"
 arch="all"

main/po4a/APKBUILD

 # Contributor: Leo <thinkabit.ukim@gmail.com>
-# Maintainer: Christian Kampka <christian@kampka.net>
+# Contributor: Christian Kampka <christian@kampka.net>
+# Maintainer:
 pkgname=po4a
 pkgver=0.62
-pkgrel=0
+pkgrel=1
 pkgdesc="Tools for helping translation of documentation"
 url="https://po4a.org"
 arch="noarch"

testing/dockerize/APKBUILD

-# Maintainer: Christian Kampka <christian@kampka.net>
+# Contributor: Christian Kampka <christian@kampka.net>
+# Maintainer:
 pkgname=dockerize
 pkgver=0.6.1
-pkgrel=5
+pkgrel=6
 pkgdesc="Utility to simplify running applications in docker containers."
 url="https://github.com/jwilder/dockerize"
 arch="x86 x86_64 ppc64le"