BUG-614: convert NotificationBrokerImpl

This does a straight xtend->java conversion by moving xtend-generated
java files into the repository instead of xtend. This is the first step
in optimizing NotificationBrokerImpl.

Change-Id: Ie8dc1dfb6c5b9e80a8d79a5de31410100b35c7fc
Signed-off-by: Robert Varga <rovarga@cisco.com>
BUG-614: Hide the executor and improve logging

As part of the xtend->Java rewrite, we get rid of unnecessary
getExecutor() and improve logging a bit.

Change-Id: I9c7052472289f701a289f4ba76312fb28af18a3f
Signed-off-by: Robert Varga <rovarga@cisco.com>
BUG-614: explicitly use old constructor

This makes use of the legacy constructor until a concrete migration path
is selected.

Change-Id: I375504303c7e134f03bf649b360327e9076d2d08
Signed-off-by: Robert Varga <rovarga@cisco.com>
BUG-614: Remove xtendisms

Generated xtend code is quite verbose and sometimes the logic gets quite
obfuscated. This patch brings the code more in-line to what a programmer
might write.

Change-Id: I9a04012a2ba106082e9b1eef25bd9cb6958736cd
Signed-off-by: Robert Varga <rovarga@cisco.com>
BUG-614: No need to build a future list

It is obvious that the constructed list of futures is never going to be
used, so let's not construct it at all.

Change-Id: I506e33da52c53b5e63088a5c8ae0bb206eb6a720
Signed-off-by: Robert Varga <rovarga@cisco.com>
BUG-614: do not use xtend's library

Convert from using xtendlib to using guava directly.

Change-Id: Ic72af54e0b1480658fb4067821969419bbab2e8e
Signed-off-by: Robert Varga <rovarga@cisco.com>
BUG-614: degrade NotifyTask to Runnable

The call() method always returned null anyway, so we might as well make it
Runnable.

Change-Id: I6be36490aba33ba1bf4b205ba4d9b0aa8160dbdf
Signed-off-by: Robert Varga <rovarga@cisco.com>