Add libcgroup to build dependencies in *.spec.
Generic streams, part two.

Actors can now freely send and receive any type of message they can
dream about, without locking onto a single streaming interface.
Drop removed includes.
Fixed building on GCC 4.4.
Move service interfaces to their headers.
Even more proper place for service interfaces!
Migrate to the new generic streams.
Cleanup.
Blocking slots do not require their own serializers.
Merge pull request #64 from andrusha97/rhel-building-fix

Add libcgroup to build dependencies in *.spec.
Major cleanup.

* Drivers are gone.
* Locator now uses the native RPC mechanics for remoting.
* All the Node Service stuff is moved to the respective directories.
* Archive support is now a part of Process Isolate.
Drivers are gone even from the Manifest.
Enable keepalive probes.
Merge branch 'master' of github.com:cocaine/cocaine-core
Fixed building on GCC 4.4.
Fixed a SIGSEGV during synchronization.
Locator remote client streaming fixes.
More naming changes.