Android: Improve "Add new AVD" dialog

* Re-organize the implementation to create a new AVD
* Use SystemImage instead of SdKPlatform because now
an SdkPlatform can be installed partially with a SystemImage.
The current implementation does not consider the this case,
thus we end up with an uncomplete list of installed system images.
* Add Device definitions with categories (phone, tablet, tv, etc.)
to the creation process (check -d arg in avdmanager create avd).

Task-number: QTCREATORBUG-23284
Change-Id: Id02a71ad452fb423fa2781d06ef3fcf2afa328a9
Reviewed-by: Alessandro Portale <alessandro.portale@qt.io>

src/plugins/android/androidtoolmanager.cpp

@@ -148,7 +148,7 @@ CreateAvdInfo AndroidToolManager::createAvdImpl(CreateAvdInfo info, FilePath and
     proc.setProcessEnvironment(env);
     QStringList arguments;
     arguments << QLatin1String("create") << QLatin1String("avd")
-              << QLatin1String("-t") << AndroidConfig::apiLevelNameFor(info.sdkPlatform)
+              << QLatin1String("-t") << QString("android-%1").arg(info.systemImage->apiLevel())
               << QLatin1String("-n") << info.name
               << QLatin1String("-b") << info.abi;
     if (info.sdcardSize > 0)