ace's grafana reads InfluxDB through a data source somebody typed into
its database: a LAN address, a database InfluxDB 2 does not have, and a
password for a v1 user of an earlier instance. Nothing in the mesh knew
it existed, so migrating influxdb could only break it further.
grafana now requires influxdb-api, contributes read access, and the mesh
renders a provisioning file grafana reads at start: the address, port,
org's default bucket (as the InfluxQL database) and its own login from
the binding, the password by $__file from the pair credential the mesh
delivers, 0400 for grafana's uid 472. It is a data source of its own
name and uid, read-only in the UI and not the default, so the data
source a person made is never overwritten; a changed binding or a
rotated password restarts grafana, which re-reads the file.
Includes #152 (merged into this branch): influxdb provides influxdb-api.
jschoubben
d2f03736fa