fix: refactored urls and views
add: flotjs example + middleware for cors and rest api for instruments
Minor changes

* changed Bootstrap theme
* fixed buggy activity save method
* improved test coverage
Expose name parameter for companies REST API.
Support cascade remove on associations.
Update README to execute default maven goal.
Exercise 1: add autofocus.
Exercise 1 solution.
Exercise 2 start (TODO: add activitiesTest)
Exercise 2 solution