Remove FastDelegate demo

Remove FastDelegate demo

[Issue#]   LINUXWRT-1061
[Problem]  Remove FastDelegate
[Cause]    Licesing issues
[Solution] Remove references to FastDelegate

[Verification]
1. Build repository with tests
2. Run on DUT command `wrt-commons-tests-event --output=text`.
   The same number of tests should pass after and before applying the change

[Remarks]
This is a part of a larger change (see LINUXWRT-1061 for details).

Change-Id: I13381b9966b8fe76de460ac2107caf2644f04e54