Feature/report reformulation

This MR is related to issue !109, in which the main goal is to reformat the report using Bootstrap - imported in cara/apps/calculator/templates/base/calculator.report.html.j2, which shall be modified according to issue !179.

So far, this MR tests a new structure for the report so that it becomes more user friendly and responsive.

The report is now divided in three tabs - Results, Input Data - to better separate the input from the output results - and Applicable rules. The Results tab has collapse components for each of the sections - Results and Alternative scenarios.

All the logic behind the components position in the report is based on flex classes. I've added some alerts as well as one animation for the COVID level.