Added message system, so it's possible now so create a some sort of network
between programm components. Network consists of Proxies(Activities),
Points(Fragments) and Nodes (Views). Proxies are connected by default.
They use broadcast protocol to communicate. Points connect them selfs
to proxies automatically in onCreateView(...) So, the user should
only connect Nodes to Points. After that, the full network is built.
Message can have several destinations. After message reaches all it's
destinations it stops to deliver, but only in context of one activity.

Added prototype of Course info page. Design is modern "card-style".
Refactoring of App Network. Added JavaDoc.
Refactoring of broadcast messages, javadoc, some bug fixes.
Updated screenshots and README.md
Readme.md update