[FEATURE] New plugins and plugin improvements

[SnirShechter]

Notify plugin improvements

Allow subscribing to the training via push notifications without entering the tracking URL:

• Website: Add the user's push notifications token to the UI and allow to copy it
• NotifyPlugin: allow passing that token as an argument and POSTing it to the training-start function
• training-start should automatically subscribe that token to the specific training, thus subscribing the user's device without him needing to enter the tracking url.

SMS plugin

A plugin which sends an SMS on training end

• Create a plugin which receives an array of numbers and POSTs a netlify function when done
  Code example:

plugins_manager.register_plugin(SmsPlugin(phones=["..."]))

• Create a netlify function to send an SMS regarding a finished training
  • Args: trainingId, startedAt, endedAt
  • Returns: 200 OK
• Website: The email section in the training page should have another tab for entering a phone number

Email plugin

A plugin which sends an Email on training end

• Create a plugin which receives an array of emails and POSTs a netlify function when done
  Code example:

plugins_manager.register_plugin(EmailPlugin(emails=["..."]))

• Create a netlify function to send an Email regarding a finished training
  • Args: trainingId, startedAt, endedAt
  • Returns: 200 OK