Refactoring controllers and views to use the strategy for requisitions.

I'm having issues loading the app on the browser. Apparently, there is a
problem with the load order of the JS files, but all the tests are
passing without issues.
Fixing the loading issue.

Now, the filter is not working because it was designed to work with
arrays, and the new model returns a map. Probably I should go back to
arrays.
Refactoring the code to use arrays for requisitions and nodes.
Refactoring assets and categories to be a set of objects.

Also fixing some broken features.