* allows corrugated box fee to be set as a default company cost with a
  default value of 0.0
* updates ProfitAndLoss object to pull corrugated box fee value from
  CompanyCost value set by admin (or uses 0.0 as a default)
pt-79811708 updates to reports
  * ensures all currency values are displayed in "$12.34" format
  * adds text-only email templates for all mailers
  * removes "inline" attachments from report mailers
Merge branch 'profit-and-loss-report' into staging

Conflicts:
	app/mailers/orders_report_mailer.rb
	app/mailers/product_sales_report_mailer.rb