Revert "remove user and users cookbooks from site-cookbooks, manage play user in platform cookbook"

This reverts commit a0ad6bad23f17a9aac81fbfd0fb5298ad14da866.
Revert "remove platform::rubygems, users and user recipes from platform role"

This reverts commit 0f5252a9855c52a037b1a4cf1eb10a851fb114b8.
Revert "remove newrelic cookbook and provide license keys in environment attributes"

This reverts commit a4fd40a0cdfe4ce658c1e3110d37495930816360.