Create install guide

[ovidiuch]

• [x] Add start instructions in README
• [x] Clean up install script if needed, add a PATH variable in the README instructions
• Remove any password and keys, work out some config file
  • [x] publickey
  • [x] MongoHQ
  • [x] Filepicker?
  • [x] Mailgun
• [x] Sort out Mongo dumps, add them in the install process
• [x] Add info about creating a root user
• [x] Separate cron instructions from README - Remove altogether, even in production, see if it ever crashes again
• [x] Add phantomjs instructions to README - Are there any? Sure
• [x] Add structure instructions
  • BackboneRouter
  • ReactiveTemplate
  • MeteorModel

[ovidiuch]

Create config file for Filepicker and Mailgun, as ignored file with .example versioned