Fix the URLs for courses

[anandology]

We would like to change the current URL structure as described below:

course pages
current: /courses/course?course=the-joy-of-programming
expected: ``/courses/the-joy-of-programming`

topic pages
current: /courses/topic?course=the-joy-of-programming&topic=getting-started
expected: /courses/the-joy-of-programming/getting-started

I think we should be able to use website_route_rules in hooks to achieve this.