Django views — improve the intro paragraph

[Oktosha]

I made the intro to the chapter more precise, more clear and more technical.

I split what the view does in 3 clear steps. Each step contains one highlighted technical word (request, model, template) which makes it easier to understand which technical thing is responsible for what. The first step acknowledges that the views receive request data as a parameter. The previous version wasn't explicit about it but I think it is important because the request is a parameter of a function we are about to write. I added an example of what does "logic" mean in the context of "views are where we put the logic of our application" to the second step. The third step is about filling a template. I think "filling a template" is better wording than "passing it to a template".

I rewrote the words "just Python functions that are a little bit more complicated than the ones we wrote" to "Technically, views are Python functions, exactly like the ones we wrote in the Introduction to Python chapter. These functions take request as a parameter and return HttpResponse". The new wording avoids the word "just" and instead of being vague tells what the difference is between the old functions and the new ones. The resulting paragraph sounds quite technical but I think it comes together nicely with the explanation of the code. The participants will see the request in the parameters and their recognition will click because they read about it earlier.