added scheduler design change, marked done areas as completed. moved java7 as DescripTor 2.0.0 will use java8 ([diff](https://trac.torproject.org/projects/tor/wiki/doc/CollecTor/Improvements?action=diff&version=41)) URL: https://trac.torproject.org/projects/tor/wiki/doc/CollecTor/Improvements?version=41