Description of problem:

  The package installs a systemd service unit file in "/etc/systemd/system/"
  which may clash with user-defined service unit files. That directory is
  reserved for user-defined systemd service unit files, and the ones installed
  by packages should go in "/usr/lib/systemd/system/".

Version-Release number of selected component (if applicable):

  1.2.2-1.el7

How reproducible:

  100%

Steps to Reproduce:
1. yum install golang-github-prometheus-node-exporter

Actual results:

  The "node_exporter.service" file is installed in "/etc/systemd/system/".

Expected results:

  The "node_exporter.service" file should be installed in
  "/usr/lib/systemd/system/".

Additional info:

  N/A