Add missing system services

Lot of system services were missing which are added in newer Android
versions. Now AndroidAnnotations support those. Also added tests for all
services, and commented out those which cannot be tested due to Android
version or Robolectric issues.
Use both JDK7 and JDK8 in Travis
Fix javadoc compilation errors on jdk8
Merge pull request #1168 from nbelikov/1163_javadoc_for_jdk8

Fix JavaDoc compilation errors on JDK8
Merge pull request #1164 from WonderCsabo/travisJdk8

Use both JDK7 and JDK8 in Travis
Only download the binary distribution of Gradle wrapper
fix: generic issues in EFragment
Merge pull request #1117 from Artyomcool/1077-fragment-generics

fix: generic issues in EFragment
Clean contentView_ reference in onDestroyView()

If setRetainInstance(true) has been set on the fragment or
addToBackStack() was applied to FragmentTransaction, the fragment won't be
destroyed and will keep the reference to its parent view in contentView_
and could lead to memory leak.

This change implements onDestroyView() which cleans the reference.
However, the developer is still responsible for cleaning up the injected
views, because otherwise a (badly implemented) background task may get a
NullPointerException.
Merge pull request #1171 from nbelikov/933_efragment_ondestroyview2

Clean contentView_ reference in onDestroyView()
Merge pull request #1151 from WonderCsabo/addMissingSystemServices

Add missing system services
Upgrade to Spring for Android 1.0.1
Add forward support for RestTemplate changes in Spring for Android 2.0