switch parent pom reference everywhere to 28 where it was 27 before
this can be safely done because the only difference between 27 and 28 is an updated maven-source-plugin (fix heap space error)

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1756968 13f79535-47bb-0310-9956-ffa450edef68
1 file changed
tree: 074d0b9565f73b6ea5587b64a0cad5d79daf21b9
  1. src/
  2. pom.xml
  3. README.txt