Overhaul stale keys for labels and code reduction

[rcgottlieb]

Changes proposed in this pull request:

• This is the first step in the overhaul of stale keys, which is to use a python client library to talk directly to the pushgateway
• Many of the changes are around removing the manual process using the requests python library
• The ORM was changed out to a more manageable SQLAlchemy library with Alembic
• The other changes are to bring in two new labels warn date and violation date as well as code cleanup

security considerations

Better security as there will be less code

[rcgottlieb]

closing this in favor of removing the database and creating a new PR