Revert "(SERVER-2098) Remove jrjackson gem"
Revert "(SERVER-2098) Remove jrjackson gem"

This reverts commit c7cb533eb2df9840d3c5d66dd832a5f6f1b5291a, readding
the JrJackson gem now that we are properly configured to not parse
extreme numbers as BigDecimals.

puppetlabs/puppet-server,puppetlabs/puppetserver,puppetlabs/puppet-server,puppetlabs/puppetserver,puppetlabs/puppet-server,puppetlabs/puppetserver,puppetlabs/puppetserver