shill: Add Technology class

Move Technology enum out into its own class, and create static
functions for converting between these and strings.

BUG=chromium-os:20114
TEST=Rerun unit tests

Change-Id: I9e3aea44e5d0b14d844328f023b01d7f8ea04c42
Reviewed-on: http://gerrit.chromium.org/gerrit/8204
Reviewed-by: Paul Stewart <pstew@chromium.org>
Tested-by: Paul Stewart <pstew@chromium.org>
diff --git a/device_unittest.cc b/device_unittest.cc
index 1270a49..1980929 100644
--- a/device_unittest.cc
+++ b/device_unittest.cc
@@ -118,7 +118,7 @@
 }
 
 TEST_F(DeviceTest, TechnologyIs) {
-  EXPECT_FALSE(device_->TechnologyIs(Device::kEthernet));
+  EXPECT_FALSE(device_->TechnologyIs(Technology::kEthernet));
 }
 
 TEST_F(DeviceTest, DestroyIPConfig) {