Layoutlib Create: Remove references to non-std Java classes.

Do not add the non-standard Java classes. Updates the references to all
non-standard classes to new classes in
com.android.tools.layoulib.create package. This also treats
java.lang.AutoCloseable which is part of Java 7 similarly so that we can
still run on Java 6.

Change-Id: Iac5b272652e2780c9bb72d19f415d150948ca589