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

Today users need to use some custom process of their own design to move files onto the same machine as heartbeat for synthetic suites. This won't work for cloud and is a waste of effort given that most people can / will use git.

Describe the solution you'd like

We should make it possible for heartbeat to download remote zip files (authenticated via basic auth / TLS). The syntax could be as simple as:

synthetic_suites:
- type: git
  url: https://github.com/elastic/synthetics/archive/master.zip
  username: myuser
  password: mypassword
  directory: examples