Add the Guava library to the tools

This changeset adds the Guava library to ADT and lint. (It is also a
prerequisite for the Lombok AST library which is added by a later CL.)

This changeset also uses the library in a few simple ways: It replaces
some custom I/O and collections code with calls into the equivalent
Guava methods, and it also adds the @Beta annotation on the various
"API" classes which are not yet stable.

Change-Id: I2f50febfa075c32818404e888578a2e1e447d408
diff --git a/build/tools.atree b/build/tools.atree
index 30aaec1..39deb4b 100644
--- a/build/tools.atree
+++ b/build/tools.atree
@@ -128,6 +128,7 @@
 framework/swing-worker-1.1.jar                                tools/lib/swing-worker-1.1.jar
 prebuilts/tools/common/asm-tools/asm-4.0.jar                  tools/lib/asm-4.0.jar
 prebuilts/tools/common/asm-tools/asm-tree-4.0.jar             tools/lib/asm-tree-4.0.jar
+prebuilts/tools/common/guava-tools/guava-10.0.1.jar           tools/lib/guava-10.0.1.jar
 
 # Proguard
 external/proguard/docs/license.html                           tools/proguard/license.html