NEUROP-1017

• Added possibility to select if send via sendgrid or smtp for main system function

• Adapt code to send parameter to Sendgrid API creating a queue row

• Create a cronjob that periodically (about every 1 minute) send unsent sendgrid_queue rows

NEUROP-1020

• Created templates directly in sendgrid site
• Created only EN version for now
• Created checkout, checkout client, quickpayment, clicard payment, memebership payment, orders payment, user management, company invitation, fundraiser payment, contact, client invoice

NEUROP-990

• Added a checkout configuration settings in Checkout menu where the company itself can choose which payment flow have to follow their payment
• Revise the flow for every payment integrator