Write custom os-release (closes #324)
This is the content of /etc/os-release generated using this branch
PRETTY_NAME="postmarketOS 0.2.0"
NAME="postmarketOS"
VERSION_ID="0.2.0"
VERSION="0.2.0-783a0dde"
ID="postmarketos"
ID_LIKE="alpine"
HOME_URL="http://www.postmarketos.org/"
SUPPORT_URL="https://github.com/postmarketOS/"
BUG_REPORT_URL="https://github.com/postmarketOS/"
PMOS_HASH="783a0dde1645b2d6c9ebaa434206291b304c324c"