java: Add helper class to create Json like list

This helper class is used when it is needed to create an array or an
object in a Json like format.

Signed-off-by: Amnon Heiman <amnon@cloudius-systems.com>
Java Json generator: Add a Helper class for JSON generator

The JavaInfo class retrieve information from the java and pass it to the
C++.  Some of the information is in a json format.

This helper class add some static method to create JSON formatted
string.

Signed-off-by: Amnon Heiman <amnon@cloudius-systems.com>
java: JavaInfo Garbage collection information

This is a helper class to holds the garbage collection information, it
simplified getting the data in the c++ side.

Signed-off-by: Amnon Heiman <amnon@cloudius-systems.com>
java: Adding the JavaIno class

The JavaInfo simplify getting information from the java and return it
via the JNI to the API.

It sets a simple front end for the internal java information.

Currently it support get and set mbean information, get the garbage
collection information and system properties.

Signed-off-by: Amnon Heiman <amnon@cloudius-systems.com>
java: add an interface for the java from the api

The API requires to retrieve and modify information in the jvm. To
simplify this the java_api is used as a C++ front-end to the java, it is
backed up by a java class (JavaInfo) that acts as a front-end of the
java.

Signed-off-by: Amnon Heiman <amnon@cloudius-systems.com>
java: set the JavaVM in the java_api

The java_api used by the API uses JNI to connect to the running jvm. It
needs the JavaVM pointer to get be able to connect to the JVM.

The JavaVM is been set after the jvm is created.

Signed-off-by: Amnon Heiman <amnon@cloudius-systems.com>
build.mk: Add the java_api to the compilation and packaging

The java_api.cc is a helper class that the API use to get information
from the java. It need to be compiled and added to the image.

Signed-off-by: Amnon Heiman <amnon@cloudius-systems.com>