Make 'Callable' message of descriptors.proto extensible, extend it in
java_descriptors.proto with a JVM signature of the member. This is needed in
order for annotation deserializer to find out which member in the compiled
bytecode corresponds to which descriptor in the hierarchy.
Create a new module 'serialization.java' containing everything related to
Java-specific serialization of descriptors.
Add an extension point to DescriptorSerializer, allowing to perform
platform-specific serialization on a callable
Major changes: ASM is switched from vanilla 3.3 to a 4.0 with renamed packages,
because this is done inside IDEA and we depend on that transitively.
Thus the jarjar renaming in build.xml, old library binaries deleted.
Also we now depend on exact IDEA build (EAP), not "last successful".
Zalim Bashorov