Add common entities and DAO objects

1. Use spring SimpleJdbcCall by invoking db functions to interact
with the db
2. Use EJB to get the DataSource for db connection
3. add two dao entities: Task and VmPolicy
4. code is packaged to a jboss deployable war file using
   maven-war-plugin

Signed-off-by: walteryang <walteryang47@users.noreply.github.com>
Add rest easy framework and jackson json provider

1. Use rest easy framework to provide the restful service
2. Use jackson provider to serialize the entities to json format

Signed-off-by: walteryang <walteryang47@users.noreply.github.com>