Switch central repo to https on branch-1

Maven central started enforcing https [1] today and branch-1 builds are failing presumably due to an older maven version.

Maven 3.2.3 [2] and later already switched the defaults, so not every one might run into this problem, depending on what mvn they are using. Jenkins jobs are hitting this, so they are likely using an older version.

[1] https://blog.sonatype.com/central-repository-moving-to-https
[2] https://issues.apache.org/jira/browse/MNG-5672