README files for the examples

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+This examples shows how to use the ODB Query Language to search the database
+for persistent objects matching certain criteria.
+
+The example consists of the following files:
+
+person.hxx
+  Header file defining the 'person' persistent class.
+
+person-odb.hxx
+person-odb.ixx
+person-odb.cxx 
+person.sql
+  The first three files contain the database support code and the last file
+  contains the database schema for the person.hxx header.
+
+  These files are generated by the ODB compiler from person.hxx using the
+  following command line:
+
+  odb -d <database> --generate-query --generate-schema person.hxx
+  
+  Where <database> stands for the database system we are using, for example,
+  'mysql'.
+
+database.hxx
+  Contains the create_database() function which instantiates the concrete
+  database class corresponding to the database system we are using.
+
+driver.cxx
+  Driver for the example. It includes the person.hxx and person-odb.hxx
+  headers to gain access to the 'person' class and the database support
+  code for this class. It also includes database.hxx for the 
+  create_database() function declaration.
+    
+  In main() the driver first calls create_database() to obtain the database
+  instance. It then persists a number of 'person' objects in the database
+  and executes a number of queries to find objects matching various criteria.
+
+To run the example we first need to create the database schema. Using MySQL
+as an example, this can be achieved with the following command:
+
+mysql --user=odb_test --database=odb_test < person.sql
+
+Here we use 'odb_test' as the database login and also 'odb_test' as the
+database name.
+
+Once the database schema is ready, we can run the example (using MySQL as
+the database):
+
+./driver --user odb_test --database odb_test
+