Allow to parse price functions
Add tests to check price function parsing
Update README.md
Add support for price function charging
Add tests for checking price function charging
Merge branch 'feature-complex-pricing' into develop
Merge branch 'develop' of https://github.com/conwetlab/wstore into develop
Fix minor bug
Add support for multiple price plans
Add tests to check multiple price plans
Fix bug in usdl validation
Add form for selecting the price plan in purchases
Allow the developer role for organizations
Update README file
Refactor paypal client
Adapt charging tests to paypal client refactor
Update payment template style
Improve charging views auth control
Fix bug with redirection URL encoding
Include API for deleting resources