Move to gradle 3.0, tools 2.2-beta1

Support lib was stuck in tools 2.2-alpha due to a bug in gradle 2.14
(tools 2.2-beta depends on gradle 2.14).

The bug is resolved in gradle 3.0 and tools team suggested us to move
to 3.0.

I've also added some sane defaults to gradle-properties to get faster
builds with in-process dexing and gradle daemon usage

Bug: 30160196
Gradle Bug: https://code.google.com/p/android/issues/detail?id=219034
Change-Id: I6a8c310dd252d160565b6bd57635a8d4ee41dc6b
diff --git a/gradle.properties b/gradle.properties
new file mode 100644
index 0000000..34b3995
--- /dev/null
+++ b/gradle.properties
@@ -0,0 +1,3 @@
+org.gradle.jvmargs=-Xmx3g
+org.gradle.daemon=true
+org.gradle.configureondemand=true
\ No newline at end of file