[zanata/zanata-parent] c1d2b2: Update maven-site-plugin to version 3.4

[GitHub]

  Branch: refs/heads/update-mvn-site
  Home:   https://github.com/zanata/zanata-parent
  Commit: c1d2b273ef02405ab79cc9195e0cbc37516e5b41
      https://github.com/zanata/zanata-parent/commit/c1d2b273ef02405ab79cc9195e0cbc37516e5b41
  Author: David Mason <drdmason at gmail.com>
  Date:   2014-12-11 (Thu, 11 Dec 2014)

  Changed paths:
    M pom.xml

  Log Message:
  -----------
  Update maven-site-plugin to version 3.4

This is needed for running `mvn site` with newer versions of maven,
otherwise an exception is generated by a missing class.