refactor(backend): removed dynamic imports 🎊

* Removed all dynamic imports to have more standard Django infrastructre and ease future refactoring
* Removed now useless config files
* Returns the list of available endpoints to the frontend directly from the html
* updated documentation accordingly

Fixes #95
6 jobs for !81 with refactor/backend in 8 minutes and 51 seconds
detached
Status Job ID Name Coverage
  Check
passed #490645
docker
check_back

00:03:17

passed #490646
docker
check_front

00:02:37

 
  Test
passed #490647
docker
test_back

00:01:00

89.0%
passed #490648
docker
test_frontend

00:00:52

 
  Lint
passed #490650
docker
eslint

00:00:49

passed #490649
docker
flake8

00:00:13