* apply black formatting to sponsors application

* initial modeling for sponsorships revamp

* add fixtures with rough draft of sponsor programs, levels, benefits

* update modeling with capacity and make Django admin rendering a bit nicer

* tidy up benefit admin list

* New form to list sponsorship benefits

* Simplest FormView so I can access the form

* Split benefits by programs

* Change fieldname

* Organize levels' benefits in the HTML

* JS code to auto-fill the benefits from level

* adjust modeling based on further clarification

rename "Levels" to "Packages"
-----------------------------
we will abstract levels as packages for now and just name them as such "Diamond Sponsorship Level"

Benefits: minimum_level -> package_only
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rather than specifying a minimum level, these benefits should be selectable only via choosing a package

Benefits: add "new" flag
------------------------
this should render a "New For This Year" badge next to benefits where selected

Benefits: "soft" capacities
---------------------------
for future implementation, some capacities are soft in the sense that we will allow people to "register interest" when they are exhausted

* Remove empty choice from the frontend

* Clear form button

* Unit test the helper property

* Implement conflict behavior in the frontend

* Backend validation on benefits conflicts

* New view to calc the benefits cost

* Run black

* Safeguard if internal_value is not set

* Fix element definition

* Display sponsorship cost in the frontend

* Only display price if level changes

* Move JS code to specific file

* Option label should be benefit's name

* Better display for packages select

* Organize benefits in columns

* Disable active labels if checkbox wasn't checked

* Display benefits checkboxes manually

* Disable packages only benefits

* Disable choices if no available quantity

* Field shouldn't be required in django admin

* Better control of cost message's update

* Fits better in mobile

* Labels should be updated even if unselect

* Install font awesome

* Refactoring

* Display icons and legend

* Improve benefits admin

* Render packages info in html using context data

* Fetch package cost from html tag attribute

* Remove price calculator view

* Remove reference for unexisting named url

* Unit test package only validation

* Validate benefits capacity

* Remove form code that was moved to view's context

* Unit test invalid post scenario

* Unit test models

* Code format

* Use package attr to display cost

* Only staff users can acess sponsorship application form

Co-authored-by: Bernardo Fontes <[email protected]>