Notify admin on new proposals

[zerothabhishek]

A notification (email) should be sent to the admin/staff when a new proposal arrives. Only the staff associated with the conference in question should be notified.

This will help the CFP-volunteering team to react faster, and also to control spam proposals

[krtkvrm]

@zerothabhishek Do we need to extend the existing feature of send_mail_for_new_proposal? Ref: junction/proposals/views.py#L157

[zerothabhishek]

@vkartik97 we need this to notify the staff associated with the conf. send_mail_for_new_proposal notifies the reviewers. We'll probably need a new function for this.

[angad277]

Hello, is this issue still open?