Implement {Available|Connected|Enabled}Technolgies and DefaultTechnology

This is Part 1 of a series of changes required for the Manager to generate
the right set of DBus events allowing shill to properly tell Chrome about
connectivity.

Some other side-effects in the change (needed to implement the above):
- Emit these manager properties over DBus everytime we re-sort the Service
  vector.
- Add a technology data member to Device, this allows easy enumeration of
  technologies.
- Add interface for getting a handle to the selected service on a device.
- Map connected state to online instead of ready state. This is needed for
  so that Chrome doesn't wait for the portal detection code to switch the
  state from ready->online.
- Default set the ethernet service as connectable.

BUG=chromium-os:14887
TEST=1) manual test to verify shill properly configures the ethernet
     device and Chrome correctly detects that.
     2) new unit tests

Change-Id: Ib10f2f0836f8d4aacaad1491f58ed9b3b5d37e7d
Reviewed-on: https://gerrit.chromium.org/gerrit/12019
Tested-by: Gaurav Shah <gauravsh@chromium.org>
Reviewed-by: mukesh agrawal <quiche@chromium.org>
diff --git a/cellular_service.cc b/cellular_service.cc
index d27a360..2daf880 100644
--- a/cellular_service.cc
+++ b/cellular_service.cc
@@ -24,7 +24,7 @@
                                  EventDispatcher *dispatcher,
                                  Manager *manager,
                                  const CellularRefPtr &device)
-    : Service(control_interface, dispatcher, manager, flimflam::kTypeCellular),
+    : Service(control_interface, dispatcher, manager, Technology::kCellular),
       strength_(0),
       cellular_(device) {
   PropertyStore *store = this->mutable_store();