help or request more information about alerts when they arrive

[stratanic]

Is your feature request related to a problem? Please describe.
Hello,

I use Prometheus and alertmanager with Alerta (and InfluxDB) , but Alertmanager is very limited without templating in Alertmanager or the concept of the tools.
there is a way to have in column description "Alerta" : the result of 2 or 3 query (for have more information on a alert),
and i don't like the "humanize" function of prometheus ( I preferd for disk data : "Mo" or "Mega" than "Mi" or "Gi" ) .

sample :
description : Warning on the server 'SRV212': Only 253 Mi of free disk space remains, representing 3% of the total 10 GB disk space.

Describe the solution you'd like
templating enable for the webhook in alertmanager (for alerta)